1X  \  7  $ 


U.  S.  DEPARTMENT  OF  AGRICULTURE, 

BUREAU  OF  ENTOMOLOGY— BULLETIN  No.  78  (Revised). 

L.  O.  HOWARD,  Entomologist  and  Chief  of  Bureau. 


ECONOMIC  LOSS  TO  THE  PEOPLE  OF  THE 

UNITED  STATES  THROUGH  INSECTS 

THAT  CARRY  DISEASE. 


BY 


L.  O.  HOWARD,  Ph.  D. 

Entomologist  and  Chief  of  Bureau. 


Issued  May  27,  1909. 


WASHINGTON: 

GOVKKXMKNT     PRINTING     OFFICE, 

1909. 


U.  S.  DEPARTMENT   OF  AGRICULTURE, 

BUREAU  OF  ENTOMOLOGY— BULLETIN  No.  78  (Revised). 

L.  O.  HOWARD.  Entomologist  and  Chief  of  Bureau. 


ECONOMIC  LOSS  TO  THE  PEOPLE  OF  THE 

UNITED  STATES  THROUGH  INSECTS 

THAT  CARRY  DISEASE. 


BY 


L.  O.  HOWARD,  Ph.  D. 

Entomologist  and  Chief  of  Bureau. 


Issued  May  27,  1900. 


WASHINGTON: 

GOVERNMENT    PRINTING     OFFICE 

1909. 


BUREA  U  OF  ENTOMOLOGY. 

L.  O.  Howard,  Entomologist  and  Chief  of  Bureau. 

C.  L.  Marl att,  Entomologist  and  Acting  Chief  in  absence,  of  Chief. 

R.  S.  Clifton,  Executive  Assistant. 

C.J.  Gilliss,  Chief  Clerk. 

F.  H.  Chittenden,  in  charge  of  truck  crop  and  special  insect  investigations. 
A.  D.  Hopkins,  in  charge  of  forest  insect  investigations. 

W.  D.  Hunter,  in  charge  of  southern  field  crop  insect  and  tick  investigations. 
F.  M.  Webster,  in  charge  of  cereal  and  forage  plant  insect  investigations. 
A.  L.  Quaintance,  in  charge  of  deciduous  fruit  insect  investigations. 

E.  F.  Phillips,  in  charge  of  apiculture. 

D.  M.  Rogers,  in  charge  of  gipsy  moth  and  brovm-taU  moth  field  work. 
A.  W.  Morrill,  in  charge  of  white  fly  investigations. 
W.  F.  Fiske,  in  charge  of  gipsy  moth  laboratory. 

F.  C.  Bishopp,  in  charge  of  cattle  tick  life  history  investigations. 
A.  C.  Morgan,  in  charge  of  tobacco  insect  investigations. 

R.  S.  Woglum,  in  charge  of  hydrocyanic-acid  gas  investigations. 
R.  P.  Currie,  in  charge  of  editorial  work. 
Mabel  Colcord,  librarian. 
2 


LETTER  OE  TRANSMITTAL. 


U.  S.  Department  of  Agriculture, 

Bureau  of  Entomology, 
Washington,  D.  C,  April  20,  1909. 
Sir  :  I  have  the  honor  to  recommend  for  publication  as  Bulletin  78, 
revised,  of  this  Bureau  the  accompanying  slightly  revised  copy  of  the 
original  edition  of  this  bulletin,  entitled  "  Economic  Loss  to  the 
People  of  the  United  States  Through  Insects  that  Carry  Disease," 
the  supply  of  which  is  now  almost  exhausted. 

The  United  States  is  just  awakening  to  a  knowledge  of  the  disas- 
trous results  following  a  lack  of  appreciation  of  the  danger  arising 
from  the  unchecked  development  of  mosquitoes  and  the  typhoid  fly, 
and  it  is  hoped  that  this  bulletin  will  not  only  emphasize  this  danger, 
but  will  also  lend  support  to  movements,  both  local  and  widespread, 
toward  the  destruction  (often  so  easy)  of  these  carriers  of  disease. 
Respectfully, 

L.  O.  Howard, 
Entomologist  and  Chief  of  Bureau. 
Hon.  James  Wilson, 

Secretary  of  Agriculture. 


CONTENTS 


Page. 

Introduction 7 

Mosquitoes 8 

Malaria 8 

Yellow  fever 17 

Work  on  the  Isthmus  of  Panama 21 

The  typhoid  fly,  commonly  known  as  the  house  fly 23 

Endemic  disease  as  affecting  the  progress  of  nations 36 

Index 39 

5 


ECONOMIC  LOSS  TO  THE  PEOPLE  OF  THE  UNITED  STATES 
THROUGH  INSECTS  THAT  CARRY  DISEASE. 


INTRODUCTION. 

It  has  been  definitely  proven  and  is  now  generally  accepted  that 
malaria  in  its  different  forms  is  disseminated  among  the  individuals 
of  the  human  species  by  the  mosquitoes  of  the  genus  Anopheles,  and 
that  the  malarial  organism  gains  entrance  to  the  human  system,  so 
far  as  known,  only  by  the  bite  of  mosquitoes  of  this  genus.  It  has 
been  proven  with  equal  definiteness  and  has  also  become  generally 
accepted  that  yellow  fever  is  disseminated  by  the  bite  of  a  mosquito 
known  as  Stegomyia  calopus  (possibly  by  the  bites  of  other  mos- 
quitoes of  the  same  genus),  and,  so  far  as  has  been  discovered,  this 
disease  is  disseminated  only  in  this  way.  Further,  it  has  been  sci- 
entifically demonstrated  that  the  common  house  fly  is  an  active  agent 
in  the  dissemination  of  typhoid  fever,  Asiatic  cholera,  and  other 
intestinal  diseases  by  carrying  the  causative  organisms  of  these  dis- 
eases from  the  excreta  of  patients  to  the  food  supply  of  healthy  indi- 
viduals; and  that  certain  species  of  fleas  are  the  active  agents  in  the 
conveyance  of  bubonic  plague.  Moreover,  the  tropical  disease  known 
as  filariasis  is  transmitted  by  a  species  of  mosquito.  Furthermore,  it 
is  known  that  the  so-called  "  spotted  fever "  of  the  northern  Rocky 
Mountain  region  is  carried  by  a  species  of  tick ;  and  it  has  been  dem- 
onstrated that  certain  blood  diseases  may  be  carried  by  several  species 
of  biting  insects.  The  purulent  ophthalmia  of  the  Nile  basin  is 
carried  by  the  house  fly.  A  similar  disease  on  the  Fiji  Islands  is 
conveyed  by  the  same  insect.  Pink  eye  in  the  southern  United  States 
is  carried  by  minute  flies  of  the  genus  Hippelates.  The  house  fly 
has  been  shown  to  be  a  minor  factor  in  the  spread  of  tuberculosis. 
The  bedbug  has  been  connected  with  the  dissemination  of  several  dis- 
eases. Certain  biting  flies  carry  the  sleeping  sickness  in  Africa.  A 
number  of  dangerous  diseases  of  domestic  animals  are  conveyed  by 
insects.  The  literature  of  the  whole  subject  has  grown  enormously 
during  the  past  few  years,  and  the  economic  loss  to  the  human  species 
through  these  insects  is  tremendous.  At  the  same  time,  this  loss  is 
entirely  unnecessary;  the  diseases  in  question  can  be  controlled,  and 
the  suppression  of  the  conveying  insects,  so  absolutely  vital  with 
certain  of  these  diseases  and  so  important  in  the  others,  can  be  brought 
about. 


8  LOSS   THROUGH    INSECTS   THAT    CARRY    DISEASE. 

MOSQUITOES. 

Entirely  aside  from  the  loss  occasioned  by  mosquitoes  as  carriers 
of  specific  diseases,  their  abundance  brings  about  a  great  monetary 
loss  in  other  ways. 

Possibly  the  greatest  of  these  losses  ie  in  the  reduced  value  of  real 
estate  in  mosquito-infested  regions,  since  these  insects  render  abso- 
lutely uninhabitable  large  areas  of  land  available  for  suburban  homes, 
for  summer  resorts,  for  manufacturing  purposes,  and  for  agricultural 
pursuits.  The  money  loss  becomes  most  apparent  in  the  vicinity  of 
Large  centers  of  population.  The  mosquito-breeding  areas  in  the 
vicinity  of  New  York  City,  for  example,  have  prevented  the  growth 
of  paying  industries  of  various  kinds  and  have  hindered  the  proper 
development  of  large  regions  to  an  amount  which  it  is  difficult  to 
estimate  in  dollars  and  cents  and  which  is  almost  inconceivable.  The 
same  may  be  said  for  other  large  cities  near  the  seacoast.  and  even 
of  those  inland  in  low-lying  regions.  The  development  of  the  whole 
State  of  Xew  Jersey  has  been  held  back  by  the  mosquito  plague. 

Agricultural  regions  have  suffered  from  this  cause.  In  portions  of 
the  Northwestern  States  it  has  been  necessary  to  cover  the  work  horses 
in  the  field  with  sheets  during  the  day.  In  the  Gulf  region  of  Texas 
at  times  the  market  value  of  live  stock  is  greatly  reduced  by  the 
abundance  of  these  insects.  In  portions  of  southern  Xew  Jersey  there 
are  lands  eminently  adapted  to  the  dairying  industry,  and  the  markets 
of  Xew  York,  Philadelphia,  and  the  large  Xew  Jersey  cities  are  at 
hand.  In  these  localities  herds  of  cattle  have  been  repeatedly  estab- 
lished, but  the  attacks  by  swarms  of  mosquitoes  have  reduced  the  yield 
of  milk  to  such  an  extent  as  to  make  the  animals  unprofitable,  and 
dairying  has  been  abandoned  for  less  remunerative  occupations.  The 
condition  of  the  thoroughbred  race  horses  at  the  great  racing  center, 
Sheepshead  Bay.  Long  Island,  was  so  impaired  by  the  attacks  of 
mosquitoes  as  to  induce  those  interested  to  spend  many  thousands  of 
dollars  a  few  years  ago  in  an  effort  to  abate  the  pest. 

All  over  the  United  States,  for  these  insects,  and  for  the  house  fly 
as  well,  it  has  become  necessary  at  great  expense  to  screen  habitations. 
The  cost  of  screening  alone  must  sorely  exceed  ten  millions  of  dol- 
lars per  annum. 

MALARIA. 

The  west  coast  of  Africa,  portions  of  India,  and  many  other  tropi- 
cal regions  have  always,  at  least  down  to  the  present  period,  been 
practically  uninhabitable  by  civilized  man.  owing  to  the  presence 
of  pernicious  malaria.  The  industrial  and  agricultural  development 
of  Italy  has  been  hindered  to  an  incalculable  degree  by  the  prevalence 
of  malaria  in  the  southern  half  of  the  Italian  peninsula,  as  well  as  in 


MOSQUITOES   AND   MALARIA.  9 

the  valley  of  the  Po  and  elsewhere.  The  introduction  and  spread  of 
malaria  in  Greece  is  stated  by  Ronald  Ross,  and  with  strong  reasons, 
to  have  been  largely  responsible  for  the  progressive  physical  degen- 
eration of  one  of  the  strongest  races  of  the  earth. 

In  the  United  States,  malaria,  if  not  endemic,  was  early  introduced. 
The  probabilities  are  that  it  was  endemic,  and  it  is  supposed  that  the 
cause  of  the  failure  of  the  early  colonies  in  Virginia  was  due  to  this 
disease.  It  is  certain  that  malaria  retarded  in  a  marked  degree  the 
advance  of  civilization  over  the  Xorth  American  Continent,  and 
particularly  was  this  the  case  in  the  march  of  the  pioneers  through- 
out the  Middle  TTest  and  throughout  the  Gulf  States  west  to  the  Mis- 
sissippi and  beyond.  In  many  large  regions  once  malarious  the  disease 
has  lessened  greatly  in  frequency  and  virulence  owing  to  the  reclama- 
tion of  swamp  areas  and  the  lessening  of  the  number  of  the  possible 
breeding  places  of  the  malarial  mosquitoes,  but  the  disease  is  still 
enormously  prevalent,  particularly  so  in  the  southern  United  States. 
There  are  many  communities  and  many  regions  in  the  Xorth  where 
malaria  is  unknown,  but  in  many  of  these  localities  and  throughout 
many  of  these  regions  Anopheles  mosquitoes  breed,  and  the  absence 
of  malaria  means  simply  that  malarial  patients  have  not  entered  these 
regions  at  the  proper  time  pf  the  year  to  produce  a  spread  of  the 
malady.  It  has  happened  again  and  again  that  in  communities  where 
malaria  was  previously  unknown  it  has  suddenly  made  its  appearance 
and  spread  in  a  startling  manner.  These  cases  are  to  be  explained, 
as  happened  in  Brookline,  Mass.,  by  the  introduction  of  Italian  labor- 
ers, some  of  whom  were  malarious,  to  work  upon  the  reservoir;  or, 
as  happened  at  a  fashionable  summer  resort  near  Xew  York  City,  by 
the  appearance  of  a  coachman  who  had  had  malaria  elsewhere  and 
had  relapsed  at  this  place.  In  such  ways,  with  a  rapidly  increasing 
population,  malaria  is  still  spreading  in  this  country. 

To  attempt  an  estimate  of  the  economic  loss  from  the  prevalence 
of  malaria  in  the  United  States  is  to  attempt  a  most  difficult  task. 
Prof.  Irving  Fisher,  in  one  of  his  papers  before  the  recent  Inter- 
national Tuberculosis  Congress,  declared  that  tuberculosis  costs  the 
people  of  the  United  States  more  than  a  billion  dollars  each  year. 
In  this  estimate  Professor  Fisher  considered  the  death  rate  for  con- 
sumption, the  loss  of  the  earning  capacity  of  the  patients,  the  period 
of  invalidism,  and  the  amount  of  money  expended  in  the  care  of  the 
sick,  together  with  other  factors.  In  making  these  estimates  he  had 
a  much  more  definite  basis  than  can  be  gained  for  malaria.  The 
death  rate  from  malaria  (as  malaria)  is  comparatively  small  and  is 
apparently  decreasing.  Exact  figures  for  the  whole  country  are  not 
available.  From  a  table  comprising  22  cities  it  appears  that  two- 
thirds  of  the  deaths  from  malaria  in  the  United  States  occur  in  the 
South — one-third  only  in  the  Xorth.  The  death  rate  from  malaria 
83434— Bull.  78—09 2 


10 


LOSS   THROUGH    INSECTS   THAT    CARRY    DISEASE. 


by  States  is  available  only  for  the  following  registration  States: 
California.  Colorado,  Connecticut,  District  of  Columbia.  Indiana, 
Maine.  Maryland.  Massachusetts,  Michigan,  New  Hampshire.  Xew 
Jersey,  Xew  York,  Pennsylvania,  Rhode  Island,  South  Dakota,  and 
Vermont,  all  of  which  are  Northern  States.  For  these  States  the 
census  reports  from  1900  to  1907,  inclusive,  give  the  following  death 
rates: 

Table  I. — Deaths  <iu>   to  malaria  in  th<    registration  states,  1900-1907. 


Year. 

Number 
of  deaths 
from  ma- 
laria per 
100.000 
popula- 
tion. 

Total 
deaths 
from  ma- 
laria. 

Year. 

Number 
of  deaths 
from  ma- 
laria per 
100,000 
popula- 
tion. 

Total 
deaths 
from  ma- 
laria. 

1900 

7.9 
6.3 
5.4 
4.3 
4.2 

2,434 
1,791 
1,738 
1,410 
1.391 

1905 3.9 

1906 3.5 

1907 

1,321 

1901 

1.415 

1902 

1  166 

1903 

1904... 

12  666 

Estimating,  from  the  preceding  table,  the  average  annual  death 
rate  due  to  malaria  at  4.8  per  100.000  population,  and  considering 
that  the  registration  area  includes  only  16  of  the  Northern  States 
(assuming  fairly,  however,  that  the  death  rate  in  the  other  Northern 
States  is  the  same),  it  seems  reasonably  safe  to  conclude  that  the  death 
rate  from  malaria  for  the  whole  United  States  must  surely  amount 
to  15  per  100,000.  It  is  probably  greater  than  this,  since  the  statistics 
from  the  South  are  city  statistics,  and  malaria  is  really  a  country 
disease.  Thus  it  is  undoubtedly  safe  to  assume  that  the  death  rate 
for  the  whole  population  of  the  United  States  is  in  the  neighborhood 
of  15  per  100.000.  This  would  give  an  annual  death  rate  from 
malaria  of  nearly  12.000  and  a  total  number  of  deaths  for  the  8-year 
period  1900-1907  of  approximately  96,000. 

But  with  malaria  perhaps  as  with  no  other  disease  does  the  death 
rate  fail  to  indicate  the  real  loss  from  the  economic  point  of  view.  A 
man  may  suffer  from  malaria  throughout  the  greater  part  of  his  life, 
and  his  productive  capacity  may  be  reduced  from  50  to  75  per  cent, 
and  yet  ultimately  he  may  die  from  some  entirely  different  immediate 
cause.  In  fact,  the  predisposition  to  death  from  other  causes  brought 
about  by  malaria  is  so  marked  that  if.  in  the  collection  of  vital  statis- 
tics, it  were  possible  to  ascribe  the  real  influence  upon  mortality  that 
malaria  possesses,  this  disease  would  have  a  very  high  rank  in  mor- 
tality tables.  Writing  of  tropical  countries,  Sir  Patrick  Manson 
declares  that  malaria  causes  more  deaths,  and  more  predisposition  to 
death  by  inducing  cachectic  states  predisposing  to  other  affections, 
than  all  the  other  parasites  affecting  mankind  together.  Moreover, 
it  has  been  shown  that  the  average  life  of  the  worker  in  malarious 


MOSQUITOES  AND   MALARIA.  11 

places  is  shorter  and  the  infant  mortality  higher  than  in  healthy 
places. 

But,  aside  from  this  vitally  important  aspect  of  the  subject,  the 
effect  of  malaria  in  lessening  or  destroying  the  productive  capacity 
of  the  individual  is  obviously  of  the  utmost  importance,  and  upon  the 
population  of  a  malarious  region  is  enormous,  even  under  modern 
conditions  and  in  the  United  States.  It  has  been  suggested  that  the 
depopulation  of  the  once  thickly  settled  Roman  Campagna  was  due  to 
the  sudden  introduction  of  malaria  by  the  mercenaries  of  Scylla  and 
Marius.  Celli,  in  1900,  states  that  owing  to  malaria  about  5,000,000 
acres  of  land  in  Italy  remain — not  uncultivated,  but  certainly  very 
imperfectly  cultivated.  Then  also,  in  further  example,  in  quite  recent 
years  malaria  entered  and  devastated  the  islands  of  Mauritius  and 
Reunion,  practically  destroying  for  a  time  the  productiveness  of  these 
rich  colonies  of  Great  Britain  and  France. 

Creighton,  in  his  article  on  malaria  in  the  Encyclopaedia  Britannica, 
states  that  this  disease  "  has  been  estimated  to  produce  one-half  of  the 
entire  mortality  of  the  human  race;  and  inasmuch  as  it  is  the  most 
frequent  cause  of  sickness  and  death  in  those  parts  of  the  globe  that 
are  most  densely  populated,  the  estimate  may  be  taken  as  at  least 
rhetorically  correct."  a 

Is  it  possible  to  make  any  close  estimate  of  the  ratio  between  the 
number  of  deaths  from  malaria  and  the  number  of  cases  of  the  same 
malady  ?  No  perfectly  sound  basis  for  such  an  estimate  is  apparent. 
In  the  English  translation  of  Celli's  work  on  "  Malaria  According 
to  the  New  Researches,"  published  in  London  in  1900,  it  is  stated 
that  the  mortality  from  malaria  in  Italy  from  1887  to  1898  varied 
from  21,033  in  the  first-named  year  to  11,378  in  the  last-named  year, 
and  the  mean  mortality  for  the  period  is  assumed  to  be  about  15,000. 
In  1896  a  count  of  the  patients  in  the  hospitals  in  Rome  was  made, 
and  the  mortality  rate  of  7.75  per  thousand  of  the  actual  patients  was 
established.  Calculating  then  on  this  basis,  and  at  this  rate,  the  num- 
ber of  cases  per  year  for  Italy  was  placed  at  about  2,000,000.  Accord- 
ing to  this  estimate,  and  with  the  average  mortality  for  the  United 
States  of  12,000  as  above  indicated,  the  approximate  number  of 
cases  for  the  United  States  would  be  about  1,550,000.  It  seems  obvi- 
ous, however,  that  Celli,  in  using  the  basis  of  hospital  patients  only, 
must  have  underestimated  the  number  of  cases  for  the  Kingdom, 
since  of  the  people  in  the  country  suffering  from  malaria  the  propor- 
tion entering  the  hospital  must  be  relatively  small.  Therefore  the 
death  rate  from  malaria  of  malarial  patients  in  the  hospital  must  be 
greater  than  the  death  rate  from  malaria  of  the  people  who  suffer 
from  this  disease  in  the  whole  country.    In  fact,  so  great  must  this 

°  See  "  Darwinism  and  Malaria,"  by  R.  G.  Eccles,  M.  D.,  Medical  Record, 
New  York,  January  16,  1909,  pp.  85-93. 


12  LOSS   THROUGH    [NSBCTS   THAT    CARRY    DISEASE. 

discrepancy  necessarily  be  that  it  would  not  seem  at  all  unlikely  to 
the  writer  if  the  number  of  persons  suffering  from  malaria  in  Italy 
were  in  reality  nearer  3,000.000  than  2.000.000. 

The  same  argument  will  hold  for  the  United  States,  and  more 
especially  so  since  as  a  rule  malaria  in  this  country  is  of  a  lighter 
type  than  in  Italy;  in  fact  an  estimate  of  3,000.000  case^  of  malaria 
in  the  United  States  annually  is  probably  by  no  means  too  high.  It 
will  not  be  an  exaggeration  to  estimate  that  one-fourth  of  the  produc- 
tive capacity  of  an  individual  suffering  with  an  average  case  of  ma- 
laria is  lost.  Accepting  this  as  a  basis,  and  including  the  loss  through 
death,  the  cost  of  medicines,  the  losses  to  enterprises  in  malarious 
regions  through  the  difficulty  of  securing  competent  labor,  and  other 
factors,  it  is  safe  to  place  the  annual  loss  to  the  United  States  from 
malarial  disease  under  present  conditions  at  not  less  than  one  hundred 
millions  of  dollars.  Celli  has  shown  that  in  Italy  the  great  railway 
industries,  for  example,  feel  the  effect  of  malaria  greatly.  Accord- 
ing to  accurate  calculations  one  company  alone,  for  1,400  kilometers 
of  railway  and  for  6,416  workmen  in  malarious  zones,  spends  on  ac- 
count of  malaria  1.050,000  francs  a  year.  The  same  writer  states  that 
the  army  in  Italy  from  1877  to  1897  had  more  than  300,000  cases  of 
malaria. 

The  loss  to  this  country  in  the  way  of  retardation  of  the  develop- 
ment of  certain  regions,  owing  to  the  presence  of  malaria,  is  extremely 
great.  Certain  territory  containing  most  fertile  soil  and  capable  of 
the  highest  agricultural  productiveness  is  practically  abandoned. 
With  the  introduction  of  proper  drainage  measures  and  antimosquito 
work  of  other  character,  millions  of  acres  of  untold  capacity  could 
be  released  from  the  scourge  at  a  comparatively  slight  expenditure. 
These  regions  in  the  absence  of  malaria  would  have  added  millions 
upon  millions  to  the  wealth  of  the  country.  Drainage  measures  are 
now  being  initiated  by  the  United  States.  Parties  of  engineers  are 
being  sent  by  the  Government  to  make  preliminary  drainage  sur- 
ve}Ts  in  the  most  prominent  of  these  potentially  productive  regions. 
The  following  statement  concerning  the  effect  of  malaria  on  the 
progress  of  this  work  has  been  made  to  the  writer  by  Dr.  George  Otis 
Smith,  director  of  the  United  States  Geological  Survey : 

"  In  one  of  the  Southern  States  11  topographic  parties  have  been  at 
work  during  the  past  field  season.  The  full  quota  for  these  parties 
would  be  55  men,  but  I  believe  that  something  over  100  men  have 
been  employed  at  different  times  during  the  season.  While  I  have 
not  exact  figures  before  me,  I  feel  warranted  in  the  statement  that  at 
least  95  per  cent  of  these  employees  have  been  sick,  for  periods  rang- 
ing from  a  few  days  up  to  two  weeks,  in  the  hospital.  Many  of  them 
have  been  able  later  to  return  to  work,  but  at  least  30  per  cent  had 
to  leave  the  field  permanently,     Bv  reason  of  this  sickness  the  effi- 


MOSQUITOES   AND   MALARIA.  13 

ciency  of  the  parties  was  reduced,  at  a  very  conservative  estimate,  by 
25  per  cent. 

"  In  my  recent  visit  in  this  field  I  found  one  man  sick  in  each  of 
the  parties  I  saw  and  one  man  who  had  just  returned  from  the 
hospital  leaving  the  field  for  good.  A  similar  state  of  things  was 
reported  from  the  other  parties.  I  regard  the  sickness  as  practically 
all  of  a  malarial  nature,  as  extreme  care  was  taken  in  all  the  camps 
to  use  nothing  but  boiled  water  except  in  a  few  instances  where  arte- 
sian water  from  great  depths  wTas  available.  In  all  the  camps  the 
tents  have  been  screened,  and  in  every  case  where  the  topographer  has 
lived  for  any  time  '  on  the  country  '  there  has  been  infection.  As 
illustrating  the  value  of  the  precautions  generally  taken  by  our  camp 
parties,  I  might  cite  the  fact  that  last  year  in  West  Virginia  with  30 
men  living  in  camp,  with  typhoid  fever  prevalent  in  the  neighborhood, 
no  cases  developed,  while  with  6  men  living  on  the  country  where 
the  same  care  could  not  be  taken  regarding  the  water  supply,  two 
cases  of  typhoid  developed." 

In  estimating  the  weight  of  Doctor  Smith's  statement,  it  must  be 
borne  in  mind  that  the  men  of  his  field  parties  are  exceptionally  in- 
telligent and  prepared  to  take  all  ordinary  precautions. 

Throughout  the  region  in  question  malaria  is  practically  universal. 
The  railroads  suffer,  and  at  the  stations  throughout  the  territory  it  is 
practically  impossible  to  keep  operators  steadily  at  work.  This  re- 
duction in  efficiency  in  the  surveying  parties  and  in  the  local  railroad 
officials  is  moreover  probably  very  considerably  less  than  the  reduc- 
tion in  the  earning  capacity  of  the  entire  population,  which,  however, 
is  necessarily  scanty. 

In  an  excellent  paper  entitled  "  The  relation  of  malaria  to  agricul- 
tural and  other  industries  of  the  South,"  published  in  the  Popular 
Science  Monthly  for  April,  1903,  Prof.  Glenn  W.  Herrick,  then  of 
the  College  of  Agriculture  of  Mississippi,  after  a  consideration  of 
the  whole  field,  concludes  that  malaria  is  responsible  for  more  sick- 
ness among  the  white  population  of  the  South  than  any  disease  to 
wmich  it  is  now  subject.  The  following  forcible  statement  referring 
to  the  States  of  Louisiana,  Mississippi,  Alabama,  Georgia,  and  South 
Carolina  is  in  Professor  Herrick's  words: 

"  We  must  nowT  consider  briefly  what  635,000  or  a  million  cases  of 
chills  and  fevers  in  one  year  mean.  It  is  a  self-evident  truth  that  it 
means  well  for  the  physician.  But  for  laboring  men  it  means  an 
immense  loss  of  their  time  together  with  the  doctors'  fees  in  many 
instances.  If  members  of  their  families  other  than  themselves  be 
affected,  it  may  also  mean  a  loss  of  time  together  with  the  doctors' 
fees.  For  the  employer  it  means  the  loss  of  labor  at  a  time  perhaps 
when  it  would  be  of  greatest  value.  If  it  does  not  mean  the  actual 
loss  of  labor  to  the  employer  it  will  mean  a  loss  in  the  efficiency  of 


14  LOSS    THROUGH    INSECTS   THAT    CARRY    DISEASE. 

his  labor.  To  the  farmers  it  ma}^  mean  the  loss  of  their  crops  by 
want  of  cultivation.  It  will  always  mean  the  noncultivation  or 
imperfect  cultivation  of  thousands  of  acres  of  valuable  land.  It 
means  a  listless  activity  in  the  world's  work  that  counts  mightily 
against  the  wealth-producing  power  of  the  people.  Finally  it  means 
from  two  to  five  million  or  more  days  of  sickness  with  all  its  attendant 
distress,  pain  of  body,  and  mental  depression  to  some  unfortunate 
individuals  of  those  five  States." 

Referring  to  the  Delta  region  in  Mississippi,  which  lies  along  the 
Mississippi  River  in  the  western  part  of  the  State  of  Mississippi, 
extending  from  the  mouth  of  the  Yazoo  River  north  nearly  to  the 
Tennessee  line,  Herrick  says  that  it  is  the  second  best  farming  land 
in  the  world,  having  only  one  rival,  and  that  is  the  valley  of  the  Nile. 
"  Still,"  says  Herrick,  "  this  land  to-day,  or  at  least  much  of  it,  can 
be  bought  at  ten  to  twenty  dollars  an  acre.  Thousands  of  acres  in 
this  region  are  still  covered  with  the  primeval  forest,  and  the  bears 
and  deer  still  roaming  there  offer  splendid  opportunities  for  the 
chase,  as  evidenced  by  the  late  visit  of  our  Chief  Executive  to  those 
regions  for  the  purpose  of  hunting.  Why  is  not  this  land  thickly 
settled?  And  why  is  it  not  worth  from  two  to  five  hundred  dollars 
an  acre?  If  it  produces  from  one  to  two  or  more  bales  of  cotton  to 
an  acre,  and  it  does,  it  ought  to  be  worth  the  above  named  figures. 
A  bale  of  cotton  to  the  acre  can  be  produced  for  thirteen  dollars, 
leaving  a  net  profit  of  twenty  to  forty  dollars  for  each  bale,  or  forty 
to  eighty  or  more  dollars  for  each  acre  of  land  cultivated.  Moreover, 
this  land  has  been  doing  that  for  years,  and  will  do  it  for  years  to 
come,  without  the  addition  of  one  dollar's  worth  of  fertilizer.  Land 
that  will  produce  a  net  profit  of  forty  to  eighty  dollars  an  acre  is  a 
splendid  investment  at  one,  two,  or  even  three  hundred  dollars  an 
acre.  Yet  this  land  does  not  sell  in*  the  market  for  anything  like  so 
much,  because  the  demand  is  not  sufficient,  for  white  people  positively 
object  to  living  in  the  Delta  on  account  of  malarial  chills  and  fevers. 
A  man  said  to  me  not  long  ago  that  he  would  go  to  the  Delta  that  day 
if  he  were  sure  that  his  own  life  or  the  lives  of  the  members  of  his 
family  would  not  be  shortened  thereby.  There  are  thousands  exactly 
like  him,  and  the  only  reason  that  these  thousands  do  not  go  there  to 
buy  lands  and  make  homes  is  on  account  of  chills  and  fevers.  But 
there  is  a  time  coming,  and  that  not  far  distant,  when  malaria  in  the 
Delta  will  not  menace  the  would-be  inhabitants.  When  that  time 
comes  it  will  be  the  richest  and  most  populous  region  in  the  United 
States." 

Malaria  is  a  preventable  disease.  It  is  possible  for  the  human 
species  to  live  and  to  thrive  and  to  produce  in  malarious  regions,  but 
at  a  very  considerable  inconvenience  and  expense.  The  Italian  inves- 
tigators,  and  especially   Celli   and  his  staff,  have   shown  that  by 


MOSQUITOES   AND   MALARIA.  15 

screening  the  huts  of  the  peasants  on  the  Roman  Campagna  and  by 
furnishing  field  laborers  with  veils  and  gloves  when  exposed  to  the 
night  air,  it  is  possible  even  in  that  famous  hotbed  of  malaria  to 
conduct  farming  operations  with  a  minimum  of  trouble  from  the 
disease.  Moreover,  Koch  and  his  assistants  in  German  East  Africa 
have  shown  that  it  is  possible,  by  stamping  out  the  disease  among 
human  beings  by  the  free  use  of  medicine,  that  a  point  can  be  gained 
where  there  is  small  opportunity  for  the  malarial  mosquitoes  to  become 
infected.  Moreover,  the  work  of  the  parties  sent  out  by  the  Liverpool 
School  of  Tropical  Medicine  and  other  English  organizations  to  the 
west  coast  of  Africa  has  shown  that  by  the  treatment  of  malarial- 
mosquito  breeding  pools  the  pernicious  coast  fever  may  be  greatly 
reduced.  Again,  the  work  of  Englishmen  in  the  Federated  Malay 
States  has  shown  that  large  areas  may  be  practically  freed  from 
malaria.  The  most  thorough  and  the  most  satisfactory  of  all  meas- 
ures consists  in  abolishing  the  breeding  places  of  the  malarial  mos- 
quitoes. In  regions  like  the  Delta  of  the  Mississippi  this  involves 
extensive  and  systematic  drainage,  but  in  very  many  localities  where 
the  breeding  places  of  the  Anopheles  mosquitoes  can  be  easily  eradi- 
cated, where  they  are  readily  located  and  are  so  circumscribed  as  to 
admit  of  easy  treatment,  it  is  possible  to  rid  the  section  of  malaria 
at  a  comparatively  slight  expense. 

With  a  general  popular  appreciation  of  the  industrial  losses  caused 
primarily  by  the  malarial  mosquito  and  secondarily  by  the  forms 
which  do  not  carry  malaria,  as  indicated  in  the  opening  paragraphs, 
it  is  inconceivable  that  the  comparatively  inexpensive  measures  neces- 
sary should  not  be  undertaken  by  the  General  Government,  by  the 
State  governments,  and  by  the  boards  of  health  of  communities,  just 
as  it  is  inconceivable  that  the  individual  should  suffer  from  malaria 
and  from  the  attacks  of  other  mosquitoes  when  he  has  individual 
preventives  and  remedies  at  hand.  Large-scale  drainage  measures 
by  the  General  Government  involving  large  sections  of  valuable  terri- 
tory have  been  planned  and  are  practically  under  way ;  certain  States, 
notably  New  Jersey  and  New  York,  are  beginning  to  work ;  communi- 
ties all  over  the  country  through  boards  of  health  are  also  beginning 
to  take  notice,  while  popular  education  regarding  the  danger  from 
mosquitoes  and  in  regard  to  remedial  measures  is  rapidly  spreading. 
But  all  of  this  interest  should  be  intensified,  and  the  importance  of 
the  work  should  be  displayed  in  the  most  emphatic  manner,  and  relief 
from  malaria  and  other  mosquito  conditions  should  be  brought  about 
as  speedily  as  possible. 

A  few  excellent  examples  of  antimalarial  work  may  be  instanced. 

The  latest  reports  on  the  measures  taken  to  abolish  malaria  from 
Klang  and  Port  Swettenham  in  Selangor,  Federated  Malay  States, 
indicate  the  most  admirable  results.     These  measures  were  under- 


taken  first  in  1901  and  1902,  and  have  been  reported  upon  from  time 
to  time  in  the  Journal  of  Tropieal  Medicine.  The  expenditure 
undertaken  by  the  Government  with  a  view  to  improving  the  health 
of  the  inhabitants  of  these  towns  has  been  fully  justified  by  the 
results,  which  promise  to  be  of  permanent  value.  The  total  expendi- 
ture for  the  town  of  Klang  down  to  the  end  of  1905  was  £3,100 
($15,086),  and  the  annual  permanent  expenditure  is  about  £60  ($292) 
for  clearing  earth  drains  and  £210  ($1,022)  for  town  gardeners.  For 
Port  Swettenham  the  total  expenditure  to  the  end  of  1905  was  £7,000 
($34,065),  and  the  annual  cost  of  keeping  up  the  drains,  etc.,  is  ap- 
proximately £40  ($195)  for  clearing  earth  drains,  and  £100  ($487) 
for  town  gardeners. 

The  careful  tabulation  of  cases  and  deaths  and  of  the  results  of 
the  examination  of  blood  of  children  in  especially  drained  areas 
indicates  the  following  conclusions:  (1)  Measures  taken  systematically 
to  destroy  breeding  places  of  mosquitoes  in  these  towns,  the  inhabit- 
ants of  which  suffered  terribly  from  malaria,  were  followed  almost 
immediately  by  a  general  improvement  in  health  and  decrease  in 
death  rate.  (2)  That  this  was  due  directly  to  the  work  carried  out 
and  not  to  a  general  dying  out  of  malaria  in  the  district  is  clearly 
shown  by  figures  pointing  out  that  while  malaria  has  practically 
ceased  to  exist  in  the  areas  treated  it  has  actually  increased  to  a 
considerable  extent  in  other  parts  of  the  district  where  antimalarial 
measures  have  not  been  undertaken. 

The  statistics  for  1905  are  even  more  favorable  than  those  for  1902, 
which  gives  a  very  strong  evidence  in  favor  of  the  permanent  nature 
of  the  improvement  carried  out.  In  fact  it  seems  as  though  malaria 
has  been  permanently  stamped  out  at  Klang  and  Port  Swettenham 
by  work  undertaken  in  1901,  and  this  experience  in  the  Malay  States 
should  be  of  value  to  those  responsible  for  the  health  of  communities 
similarly  situated  in  many  other  parts  of  the  world. 

Another  striking  example  of  excellent  work  of  this  kind  is  found 
in  the  recently  published  report  on  the  suppression  of  malaria  in 
Ismailia,  issued  under  the  auspices  of  the  Compagnie  Universelle  du 
Canal  Maritime  de  Suez.  Ismailia  is  now  a  town  of  8,000  inhabit- 
ants. It  wras  founded  by  De  Lesseps  in  April,  1862,  on  the  borders 
of  Lake  Timsah,  which  the  Suez  Canal  crosses  at  mid-distance  be- 
tween the  Red  Sea  and  the  Mediterranean.  Malarial  fever  made  its 
appearance  in  very  severe  form  in  September,  1877,  although  the 
city  had  up  to  that  time  been  very  healthy,  and  increased  so  that 
since  1886  almost  all  of  the  inhabitants  have  suffered  from  the  fever. 
In  1901  an  attempt  to  control  the  disease  was  made  on  the  mosquito 
basis,  and  this  attempt  rapidly  and  completely  succeeded,  and  after 
two  years  of  work  all  traces  of  malaria  disappeared  from  the  city. 
The  work  was  directed  not  only  against  Anopheles  mosquitoes,  but 


MOSQUITOES   AND   YELLOW   FEVER.  17 

against  other  culicids,  and  comprised- the  drainage  of  a  large  swamp 
and  the  other  usual  measures.  The  initial  expense  amounted  to 
50,000  francs  ($9,650),  and  the  annual  expenses  since  have  amounted 
to  about  18,300  francs  ($3,532). 

The  results  may  be  summarized  about  as  follows:  Since  the  be- 
ginning of  1903  the  ordinary  mosquitoes  have  disappeared  from 
Ismailia.  Since  the  autumn  of  1903  not  a  single  larva  of  Anopheles 
has  been  found  in  the  protected  zone,  which  extends  to  the  west  for 
a  distance  of  1,000  meters  from  the  first  houses  in  the  Arabian 
quarter  and  to  the  east  for  a  distance  of  1,800  meters  from  the  first 
houses  in  the  EurojDean  quarter.  After  1902  malarial  fever  obviously 
began  to  decrease,  and  since  1903  not  a  single  neAv  case  of  malaria 
has  been  found  in  Ismailia. 

A  very  efficient  piece  of  antimalarial  work  was  accomplished  in 
Havana  during  the  American  occupation  of  1901  to  1902,  incidental 
in  a  way  to  the  work  against  yellow  fever.  An  Anopheles  brigade 
of  workmen  was  organized  under  the  sanitary  officer,  Doctor  Gorgas, 
for  work  along  the  small  streams,  irrigated  gardens,  and  similar 
places  in  the  suburbs,  and  numbered  from  50  to  300  men.  No  exten- 
sive drainage,  such  as  would  require  engineering  skill,  was  attempted, 
and  the  natural  streams  and  gutters  were  simply  cleared  of  obstruc- 
tions and  grass,  while  superficial  ditches  were  made  through  the  irri- 
gated meadows.  Among  the  suburban  truck  gardens  Anopheles  bred 
everywhere,  in  the  little  puddles  of  water,  cow  tracks,  horse  tracks, 
and  similar  depressions  in  grassy  ground.  Little  or  no  oil  was  used 
by  the  Anopheles  brigade,  since  it  was  found  in  practice  a  simple 
matter  to  drain  these  places.  At  the  end  of  the  year  it  was  very  diffi- 
cult to  find  water  containing  mosquito  larvae  anywhere  in  the  suburbs, 
and  the  effect  upon  malarial  statistics  was  striking.  In  1900,  the 
year  before  the  beginning  of  the  mosquito  work,  there  were  325 
deaths  from  malaria;  in  1901,  the  first  year  of  the  mosquito  work, 
171  deaths;  in  1902,  the  second  year  of  mosquito  work,  77  deaths* 
Since  1902  there  has  been  a  gradual  though  slower  decrease,  as  fol- 
lows: 1903,  51;  1904,  44;  1905,  32;  1906,  26;  1907,  23.  These  results, 
although  less  striking  than  those  from  Ismailia,  involved  a  smaller 
expense  in  money  and  show  surely  an  annual  saving  of  300  lives,  and 
undoubtedly  a  corresponding  decrease  in  the  number  of  malarial 
cases,  which  may  be  estimated  upon  our  earlier  basis  at  something 
less  than  40,000. 

YELLOW  FEVER. 

Yellow  fever  has  prevailed  endemically  throughout  the  West  In- 
dies and  in  certain  regions  on  the  Spanish  Main  virtually  since  the 
discovery  of  America.  Barbados,  Jamaica,  and  Cuba  suffered 
epidemics  before  the  middle  of  the  seventeenth  century.     There  were 

83434— Bull.  78—09 3 


18  LOSS    THROUGH    INSECTS   THAT    CABBY    DISEASE. 

outbreaks  in  Philadelphia,  Charleston,  and  Boston  as  early  as  1G92, 
and  for  a  hundred  years  there  were  occasional  outbreaks,  culminat- 
ing in  the  great  Philadelphia  epidemic  of  1793.  Northern  cities  were 
able,  by  rigid  quarantine  measures,  to  prevent  great  epidemics  after 
the  early  part  of  the  nineteenth  century,  but  from  the  West  Indies 
the  disease  was  occasionally  introduced  and  prevailed  from  time  to 
time  epidemically  in  the  Southern  States.  In  1853  it  raged  through- 
out this  region,  New  Orleans  alone  having  a  mortality  of  8,000.  The 
last  widespread  epidemic  occurred  in  1878,  chiefly  in  Louisiana,  Ala- 
bama, and  Mississippi,  but  spreading  up  the  Mississippi  Valley  as  far 
as  Cairo,  111.,  and  attacking  with  virulence  the  city  of  Memphis,  Tenn. 
In  this  year  there  were  125,000  cases  and  12,000  deaths.  In  1882 
there  were  192  deaths  at  Pensacola ;  in  1887,  G2  deaths  in  the  Southern 
States;  in  1893,  52  deaths;  in  1897,  484;  in  1898,  2,456  cases  with 
117  deaths;  in  1903,  139  deaths  wTere  recorded,  mostly  at  Laredo, 
Tex.,  and  in  1905  there  was  a  serious  outbreak  at  New  Orleans  and 
in  neighboring  towns,  including  one  locality  in  Mississippi,  in  which 
911  deaths  were  recorded  for  the  whole  country. 

The  actual  loss  of  life  from  yellow  fever  during  all  these  years, 
when  compared  with  the  loss  from  other  diseases,  has  been  compara- 
tively slight,  but  the  death  rate  is  perhaps  the  most  insignificant  fea- 
ture of  the  devastation  which  yellow  fever  epidemics  have  produced, 
and  the  disease  itself  has  been  but  a  small  part  of  the  affliction  which 
it  has  brought  to  the  Southern  States.  The  disease  once  discovered  in 
epidemic  form,  the  whole  country  has  become  alarmed;  commerce 
in  the  affected  region  has  come  virtually  to  a  standstill;  cities  have 
been  practically  deserted ;  people  have  died  from  exposure  in  camping 
out  in  the  highlands ;  rigid  quarantines  have  been  established ;  inno- 
cent persons  have  been  shot  while  trying  to  pass  these  quarantine 
lines;  all  industry  for  the  time  has  ceased.  The  commerce  of  the 
South  during  the  epidemic  of  1878,  for  example,  fell  off  90  per  cent, 
and  the  hardships  of  the  population  can  not  be  estimated  in  monetary 
terms.  With  such  industrial  and  commercial  conditions  existing 
from  Texas  to  South  Carolina,  many  industries  at  the  North  have 
suffered,  and,  in  fact,  the  effect  of  a  yellow  fever  summer  in  the  South 
has  been  felt  not  only  all  over  the  United  States,  but  in  many  other 
portions  of  the  world. 

All  these  conditions,  as  bad  as  they  have  been,  do  not  sum  up  the 
total  loss  to  the  national  prosperity  during  past  years.  Cities  like 
Galveston,  New  Orleans,  Mobile,  Memphis,  Jacksonville,  and  Charles- 
ton, subject  to  occasional  epidemics,  as  they  have  been  in  the  past, 
have  not  prospered  as  they  should  have  done.  Their  progress  has 
been  greatly  impeded  by  this  one  cause,  and  thus  the  industrial 
development  of  the  entire  South  has  been  greatly  retarded. 


MOSQUITOES   AXD    YELLOW    FEVER.  19 

Physicians  have  been  theorizing  about  the  cause  of  yellow  fever 
from  the  time  when  they  began  to  treat  it.  It  was  thought  by  many 
that  it  was  carried  in  the  air;  by  others  that  it  was  conveyed  by  the 
clothing,  bedding,  or  other  articles  which  had  come  in  contact  with  a 
yellow-fever  patient.  There  were  one  or  two  early  suggestions  of  the 
agency  of  mosquitoes,  but  practically  no  attention  was  paid  to  them, 
and  they  have  been  resurrected  and  considered  significant  onry  since 
the  beginning  of  the  present  century.  With  the  discovery  of  the 
agency  of  micro-organisms  in  the  causation  of  disease,  a  search  soon 
began  for  some  causative  germ.  Many  micro-organisms  were  found 
in  the  course  of  the  autopsies,  and  many  claims  Avere  put  forth  by 
investigators.  All  of  these,  however,  were  virtually  set  at  rest  by 
Sternberg  in  his  "  Report  on  the  Etiology  and  Prevention  of  Yellow 
Fever."  published  in  1890,  but  a  claim  made  by  Sanarelli  in  June, 
1897.  for  a  bacillus  which  he  called  Bacillus  Ictcroidcs  received  con- 
siderable credence,  and  in  1899  it  was  accepted  in  full  by  Wasden  and 
Geddings.  of  the  United  States  Marine-Hospital  Service,  who  re- 
ported that  they  had  found  this  bacillus  in  thirteen  or  fourteen  cases 
of  yellow  fever  in  the  city  of  Havana.  There  is  no  evidence,  how- 
ever, that  this  bacillus  has  anything  to  do  with  yellow  fever.  In  1881 
Finlay.  of  Havana,  proposed  the  theory  that  yellow  fever,  whatever 
its  cause  may  be.  is  conveyed  by  means  of  Culex  (now  Stegomyia) 
fasciatus  (now  calopus).  Subsequently  he  published  several  im- 
portant papers,  in  which  his  views  were  modified  from  time  to  time, 
and  in  the  course  of  which  he  mentioned  experiments  with  100  indi- 
viduals, producing  3  cases  of  mild  fever.  None  of  the  cases,  however, 
was  under  his  full  control,  and  the  possibility  of  other  methods  of 
contracting  the  disease  was  not  excluded.  Therefore,  his  theory, 
while  it  was  received  with  interest,  was  not  considered  to  be  proved. 

In  1900  came  the  beginning  of  the  true  demonstration.  An  army 
board  was  appointed  by  Surgeon-General  Sternberg  for  the  purpose 
of  investigating  the  acute  infectious  diseases  prevailing  in  the  island 
of  Cuba.  The  result  achieved  by  this  board,  consisting  of  Reed, 
Carroll,  Lazear,  and  Agramonte,  was  a  demonstration  that  yellow 
fever  is  carried  by  Stegomyia  calopus,  and  their  ultimate  demonstra- 
tion was  so  perfect  as  to  silence  practically  all  expert  opposition.  The 
Third  International  Sanitary  Convention  of  the  American  Republics 
unanimously  accepted  the  conclusion  that  yellow  fever  is  carried  by 
this  mosquito,  and  that  the  Stegomyia  constitutes  the  only  known 
means  by  which  the  disease  is  spread.  To-day,  after  abundant  addi- 
tional demonstration,  the  original  contention  of  Reed.  Carroll,  and 
Agramonte  (Lazear  having  died  in  the  course  of  the  experiments)  is 
a  part  of  the  accepted  knowledge  of  the  medical  world.  The  im- 
portance of  the  discovery  can  not  be  overestimated,  and  its  first 
demonstration   was  followed  by   antimosquito  measures  in  the  city 


20  LOSS    THROUGH   INSECTS   THAT    CARRY   DISEASE. 

of  Havana,  undertaken  under  the  direction  of  Gorgas.  with  startling 
results. 

Yellow  fever  had  been  endemic  in  Havana  for  more  than  one  hun- 
dred and  fifty  years,  and  Havana  was  the  principal  source  of  infec- 
tion for  the  rest  of  Cuba.  Other  towns  in  Cuba  could  have  rid 
themselves  of  the  disease  if  they  had  not  been  constantly  reinfected 
from  Havana.  By  ordinary  sanitary  measures  of  cleanliness,  im- 
proved drainage,  and  similar  means  the  death  rate  of  the  city  wTas 
reduced,  from  1898  to  1900,  from  100  per  thousand. to  22  per  thou- 
sand; but  these  measures  had  no  effect  upon  yellow  fever,  this  disease 
increasing  as  the  nonimmune  population  following  the  Spanish  war 
increased,  and  in  1900  there  was  a  severe  epidemic. 

Stegomyia  calopus  was  established  as  the  carrier  of  the  fever 
early  in  1901,  and  then  antimosquito  measures  were  immediately 
begun.  Against  adult  mosquitoes  no  general  measures  were  attemp- 
ted, although  screening  and  fumigation  were  carried  out  in  quarters 
occupied  by  yellow-fever  patients  or  that  had  been  occupied  by 
yellow -fever  patients.  It  was  found  that  the  Stegomyia  bred  prin- 
cipally in  the  rain-water  collections  in  the  city  itself.  The  city  was 
divided  into  about  30  districts,  and  to  each  district  an  inspector  and 
two  laborers  were  assigned,  each  district  containing  about  a  thousand 
houses.  An  order  was  issued  by  the  mayor  of  Havana  requiring  all 
collections  of  water  to  be  so  covered  that  mosquitoes  could  not  have 
access,  a  fine  being  imposed  in  cases  where  the  order  was  not  obeyed. 
The  health  department  covered  the  rain-water  barrels  of  poor  fami- 
lies at  public  expense.  All  cesspools  wTere  treated  with  petroleum. 
All  receptacles  containing  fresh  water  Avhich  did  not  comply  with  the 
law  were  emptied  and  on  the  second  offense  destroyed.  The  result  of 
this  work  thoroughly  done  was  to  Avipe  out  A7elloAv  fever  in  Havana, 
and  there  has  not  been  a  certain  endemic  case  since  that  time. 

In  the  New  Orleans  epidemic  of  1905,  a  striking  illustration  of  the 
value  of  this  recently  acquired  mosquito-transmission  knowledge  is  seen. 
The  presence  of  yellow  fever  in  the  city  wTas  first  recognized  about  the 
12th  of  July,  and  the  plan  of  campaign  adopted  by  the  Board  of  Health 
under  Dr.  Quitman  Kohnke,  from  the  beginning  was  based  on  the 
mosquito  conveyance  of  the  disease.  Available  funds  Avere  rapidly 
exhausted,  hoAvever,  and  on  the  12th  of  August  the  Public  Health  and 
Marine-Hospital  Service  was  put  in  charge  of  the  situation  and  pro- 
Added  with  ample  means.  By  that  time  the  increase  in  the  neAv  cases 
and  deaths  rendered  it  practically  certain  that  the  disease  Avas  as  Avide- 
spread  as  during  the  terrible  epidemic  of  1878.  There  had  been  up  to 
that  time  142  deaths  from  a  total  of  913  cases,  as  against  152  deaths 
from  a  total  of  519  cases  in  1878.  The  Avork  for  the  rest  of  the  sum- 
mer Avas  continued  with  great  energy  under  Doctor  White,  and  the 
measures  Avere  based  almost  entirely  upon  a  Avarfare  against  the  yel- 
low-fever mosquito.  The  disease  began  almost  immediately  to  abate, 
and  the  result  at  the  close  of  the  season  indicated  460  deaths,  as 
against  4,046  in   1878,  a  virtual  saving  of  over  3,500  liATes.     The 


WORK    AGAIXST    MOSQUITOES    IX    PANAMA. 


21 


following  table  of  deaths  from  yellow  fever  in  New  Orleans  from 
1847  to  1905  points  out  most  strikingly  the  value  of  this  antimosquito 
work : 

Table  II. — Comparative  table  of  deaths  from  yellow  fever  in  New  Orleans  dur- 
ing various  years. 


Month. 

Year. 

1847. 

1848. 

1863. 

1354. 

1855. 

1858. 

1867. 

1878. 

1905. 

May 

2 

31 

1,521 

5,133 

982 
147 

28  ! 

4 

June 

4 

33 

200 

467 

126 

20 

""22' 

2 

29 

532 

1,234 

490 

131 

7 

5 

382 

1,286 

874 

97 

19 

7 

2 

132 

1,140 

2,204 

1.137 

224 

15 

3 

11 

255 

1, 637 

1,072 

103 

26 

July 

74 

965 

1,100 

198 

12 

10 

445 

26 
1,025 
1,780 
1, 065 

147 
3 

35 

August 

236 

September 

107 

October 

59 

November 

23 

December 

Months  unknown 

Total 

2,804 

872 

7,  Ms 

2,425 

2,670 

4,854 

3,107 

4,046 

460 

The  epidemics  of  1818,  1854,  and  1855  are  least  comparable  with 
that  of  1905  because  they  immediately  succeeded  severe  epidemics  to 
which  were  due  very  many  immunes. 

The  population  of  Xew  Orleans  by  the  United  States  Census  was 
130,565  in  1850:  168,675  in  1860;  191.118  in  1870;  216,090  in  1880, 
and  287,101  in  1900. 

WORK   ON   THE   ISTHMUS   OF   PANAMA. 

The  United  States  Government  has  very  properly  used  the  services 
of  Colonel  Gorgas.  who  was  in  charge  of  the  eminently  successful 
work  at  Havana,  by  appointing  him  chief  sanitary  officer  of  the 
Canal  Zone  during  the  digging  of  the  canal.  In  1901  active  work  was 
begun,  and  Colonel  Gorgas  was  fortunate  in  having  the  services  of 
Mr.  Le  Prince,  who  had  been  chief  of  his  mosquito  brigades  in  Havana, 
and  therefore  was  perfectly  familiar  with  antimosquito  methods.  In 
Panama,  as  in  Havana,  the  population  had  depended  principally 
upon  rain  water  for  domestic  purposes,  so  that  every  house  had  cis- 
terns, water  barrels,  and  such  receptacles  for  catching  and  storing 
rain  water.  The  city  was  divided  up  into  small  districts  with  an  in- 
spector in  charge  of  each  district.  This  inspector  was  required  to 
cover  his  territory  at  least  twice  a  week  and  to  make  a  report  upon 
each  building  with  regard  to  its  condition  as  to  breeding  places  of 
mosquitoes.  All  the  cisterns,  water  barrels,  and  other  water  recepta- 
cles in  Panama  were  covered  as  in  Havana,  and  in  the  water  barrels 
spigots  were  inserted  so  that  the  covers  would  not  have  to  be  taken 
off.  Upon  first  inspection,  in  March.  1,000  breeding  places  were 
reported.  At  the  end  of  October  less  than  100  containing  larvae 
were  recorded.     This  gives  one  a  fair  idea  of  the  consequent  rapid 


22  IJ'SS   THROUGH    INSECTS    THAT    CABBY    DISEASE. 

decrease  in  the  Dumber  of  mosquitoes  in  the  city.  These  opera- 
tions were  directed  primarily  against  the  yellow-fever  mosquito,  and 
incidentally  against  the  other  common  species  that  inhabit  rain-water 
barrel-.    Against  the  Anopheles  in  the  suburbs  the  same  kind  of  work 

was  done  as  was  done  in  Havana,  with  exceptionally  good  results. 

The  same  operation-  were  carried  on  in  the  villages  between  Pan- 
ama and  Colon.  There  are  some  twenty  of  these  villages,  running 
from  500  to  3.000  inhabitants  each.  Not  a  single  instance  of  failure 
has  occurred  in  the  disinfection  of  these  small  town-,  and  the  result 
of  the  whole  work  has  been  the  apparent  elimination  of  yellow  fever 
and  the  very  great  reduction  of  malarial  fever. 

The  remarkable  character  of  these  results  can  only  be  judged  accu- 
rately by  comparative  methods.  It  is  well  known  that  during  the 
French  occupation  there  was  an  enormous  mortality  among  the 
European  employees,  and  this  was  a  vital  factor  in  the  failure  of  the 
work.  Exact  losses  can  not  be  estimated,  since  the  work  was  done 
under  17  different  contractors.  These  contractors  were  charged  Si 
a  day  for  every  sick  man  to  be  taken  care  of  in  the  hospital  of  the 
company.  Therefore  it  often  happened  that  when  a  man  became 
sick  his  employer  discharged  him,  so  that  he  would  not  have  to  bear 
the  expense  of  hospital  charge^.  There  was  no  police  patrol  of  the 
territory  and  many  of  these  men  died  along  the  line.  Colonel 
Gorgas  has  stated  that  the  English  consul,  who  was  at  the  Isthmus 
during  the  period  of  the  French  occupation,  is  inclined  to  think 
that  more  deaths  of  employees  occurred  out  of  the  hospital  than  in  it. 
A  great  many  were  found  to  have  died  along  the  roadside  while  en- 
deavoring to  find  their  way  to  the  city  of  Panama.  The  old  superin- 
tendent of  the  French  hospital  >tate-  that  one  day  3  of  the  medical 
staff  died  from  yellow  fever,  and  in  the  same  month  9  of  the  medical 
staff.  Thirty-six  Roman  Catholic  sisters  were  brought  over  a-  nurses, 
and  24  died  of  yellow  fever.  On  one  vessel  lv  young  French  engi- 
neer- came  over,  and  in  a  month  after  their  arrival  all  but  one  died. 

Now  that  the  relation  of  the  mosquito  to  yellow  fever  is  well  under- 
stood, it  was  found  during  the  first  two  years  under  Doctor  Gorgas 
that,  although  there  were  constantly  one  or  more  yellow-fever  cases 
in  the  hospital,  and  although  the  nurses  and  physicians  were  all  non- 
immunes, not  a  single  case  of  yellow  fever  was  contracted  in  that 
way.  The  nurses  never  seemed  to  consider  that  they  were  running 
any  risk  in  attending  yellow  fever  ca.-e>  night  and  day  in  screened 
ward-,  and  the  wives  and  families  of  officers  connected  with  the  hos- 
pital lived  about  the  ground.-,  knowing  that  yellow  fever  was  con- 
stantly being  brought  into  the  ground-  and  treated  in  near-by  build- 
Americans,  sick  from  any  cause,  had  no  fear  when  being 
treated  in  beds  immediately  adjoining  those  of  yellow-fever  pa- 
tients.    Colonel   Gorgas   and   Doctor   Carter   lived   in  the   old   ward 


THE    TYPHOID   FLY,    OR   HOUSE   FLY.  23 

used  by  the  French  for  their  officers,  and  Colonel  Gorgas  thinks  it 
safe  to  say  that  more  men  had  died  from  yellow  fever  in  that  build- 
ing under  the  French  regime  than  in  airy  other  building  of  the  same 
capacity  at  present  standing.  He  and  Doctor  Carter  had  their  wives 
and  children  with  them,  which  would  formerly' have  been  considered 
the  height  of  recklessness,  but  they  looked  upon  themselves,  under  the 
now  recognized  precautions,  as  being  as  safe,  almost,  as  they  would 
have  been  in  Philadelphia  or  Boston. 

Xo  figures  of  the  actual  cost  of  the  antimosquito  work,  either  in 
Havana  or  in  the  Panama  Canal  Zone,  are  accessible  to  the  writer, 
but  it  is  safe  to  say  that  it  was  not  exorbitant,  and  that  it  was  not 
beyond  the  means  of  any  well-to-do  community  in  tropical  regions. 

THE  TYPHOID  FLY,  COMMONLY  KNOWN  AS  THE  HOUSE  FLY. 

The  name  "  typhoid  fly  "  is  here  proposed  as  a  substitute  for  the 
name  "  house  fly."  now  in  general  use.  People  have  altogether  too 
long  considered  the  house  fly  as  a  harmless  creature,  or,  at  the  most, 
simply  a  nuisance.  "While  scientific  researches  have  shown  that  it  is 
a  most  dangerous  creature  from  the  standpoint  of  disease,  and  while 
popular  opinion  is  rapidly  being  educated  to  the  same  point,  the 
retention  of  the  name  house  fly  is  considered  inadvisable,  as  perpetu- 
ating in  some  degree  the  old  ideas.  Strictly  speaking,  the  term 
"typhoid  fly"  is  open  to  some  objection,  as  conveying  the  erroneous 
idea  that  this  fly  is  solely  responsible  for  the  spread  of  typhoid,  but 
considering  that  the  creature  is  dangerous  from  every  point  of  view, 
and  that  it  is  an  important  element  in  the  spread  of  typhoid,  it 
seems  advisable  to  give  it  a  name  which  is  almost  wholly  justified  and 
which  conveys  in  itself  the  idea  of  serious  disease.  Another  repul- 
sive name  that  might  be  given  to  it  is  "  manure  fly,"  but  recent 
researches  have  shown  that  it  is  not  confined  to  manure  as  a  breeding 
place,  although  perhaps  the  great  majority  of  these  flies  are  born 
in  horse  manure.  For  the  end  in  view.  **  typhoid  fly  "  is  considered 
the  best  name. 

The  true  connection  of  the  so-called  house  fly  with  typhoid  fever 
and  the  true  scientific  evidence  regarding  its  role  as  a  carrier  of  that 
disease  have  onhT  recently  been  worked  out.  Celli  in  1888  fed  flies 
with  pure  cultures  of  the  typhoid  bacillus,  and  examined  their 
contents  and  dejections  microscopically  and  culturally.  Inocu- 
lations of  animals  were  also  made,  proving  that  the  bacilli  which 
passed  through  flies  were  virulent.  Dr.  George  M.  Kober,  familiar 
with  Celli's  researches,  in  his  report  on  the  prevalence  of  tj^phoid 
fever  in  the  District  of  Columbia,  published  in  1895,  called  especial 
attention  to  the  danger  of  the  contamination  of  food  supplies  by 


24  LOSS    THROUGH    INSECTS    THAT    CARRY   DISEASE. 

flies  coming  from  the  excreta  of  typhoid  patients.  The  prevalence  of 
typhoid  fever  in  the  concentration  camps  of  the  United  State-  Army 
in  the  summer  of  1808  brought  about  the  appointment  of  an  army 
board  of  medical  officers  consisting  of  Drs.  Walter  Reed,  U.  S.  Arm  v. 
Victor  C.  Vaughan,  U.  S.  Volunteers,  and  E.  O.  Shakespeare,  U.  S. 
Volunteers,  to  investigate  the  causes.  The  abstract  of  the  report  of 
this  board,  published  in  11)00.  contains  (p.  183)  the  following  conclu- 
sions with  regard  to  flies  : 

"Flies  undoubtedly  served  as  carriers  of  the  infection. 

"  Flies  swarmed  over  infected  fecal  matter  in  the  pits  and  then 
visited  and  fed  upon  the  food  prepared  for  the  soldiers  at  the  mess 
tents.  In  some  instances  where  lime  had  recently  been  sprinkled 
over  the  contents  of  the  pits,  flies  with  their  feet  whitened  with  lime 
Avere  seen  walking  over  the  food. 

"  It  is  possible  for  the  fly  to  carry  the  typhoid  bacillus  in  two 
ways.  In  the  first  place,  fecal  matter  containing  the  typhoid  germ 
may  adhere  to  the  fly  and  be  mechanically  transported.  In  the 
second  place,  it  is  possible  that  the  typhoid  bacillus  may  be  carried 
in  the  digestive  organs  of  the  fly  and  may  be  deposited  with  its 
excrement." 

Doctor  Vaughan,  of  the  board  just  mentioned,  in  a  paper  read  be- 
fore the  annual  meeting  of  the  American  Medical  Association  at 
Atlantic  City,  N.  J.,  June  G,  1900,  gives  the  following  additional  rea- 
sons for  believing  that  flies  were  active  in  the  dessemination  of 
typhoid  fever: 

"  Officers  whose  mess  tents  were  protected  by  means  of  screens 
suffered  proportionately  less  from  typhoid  fever  than  did  those 
whose  tents  were  not  so  protected. 

"  Typhoid  fever  gradually  disappeared  in  the  fall  of  1898,  with 
the  approach  of  cold  weather,  and  the  consequent  disabling  of  the  fly." 

There  were  also  many  important  conclusions  which  bear  upon  the 
fly  question.  For  example,  it  was  shown  that  every  regiment  in  the 
United  States  service  in  1898  developed  typhoid  fever,  nearly  all  of 
them  within  eight  weeks  after  assembling  in  camps.  It  not  only 
appeared  in  every  regiment  in  the  service,  but  it  became  epidemic 
both  in  small  encampments  of  not  more  than  one  regiment  and  in  the 
larger  ones  consisting  of  one  or  more  corps.  All  encampments 
located  in  the  Northern  as  well  as  in  the  Southern  States  exhibited 
typhoid  in  epidemic  form.  The  miasmatic  theory  of  the  origin  of 
typhoid  fever  and  the  pythogenic  theory  °  were  not  supported  by 
the  investigations  of  the  commission,  but  the  doctrine  of  the  specific 

a  This  theory  is  founded  upon  the  belief  that  the  colon  germ  may  undergo  a 
ripening  process  by  means  of  which  its  virulence  is  so  increased  and  altered 
that  it  may  be  converted  into  the  typhoid  bacillus  or  at  least  may  become  the 
active  agent  in  the  causation  of  typhoid  fever. 


THE   TYPHOID   FLY,    OR   HOUSE   FLY.  25 

origin  of  the  fever  was  confirmed.  The  conclusion  was  reached  that 
the  fever  is  disseminated  by  the  transference  of  the  excretions  of  an 
infected  individual  to  the  alimentary  canals  of  others,  and  that  a 
man  infected  with  typhoid  fever  may  scatter  the  infection  in  every 
latrine  or  regiment  before  the  disease  is  recognized  in  himself ,  while 
germs  may  be  found  in  the  excrement  for  a  long  time  after  the 
apparently  complete  recovery  of  the  patient.  Infected  water  was 
not  an  important  factor  in  the  spread  of  typhoid  in  the  national 
encampments  of  1898,  but  about  one-fifth  of  the  soldiers  in  the 
national  encampments  in  the  United  States  during  that  summer  de- 
veloped this  disease,  while  more  than  80  per  cent  of  the  total  deaths 
were  caused  by  typhoid. 

In  1899  the  writer  began  the  study  of  the  typhoid  or  house  fly 
under  both  country  and  city  conditions.  He  made  a  rather  thorough 
investigation  of  the  insect  fauna  of  human  excrement,  and  made  a 
further  investigation  of  the  species  of  insects  that  are  attracted  to 
food  supplies  in  houses.  In  a  paper  entitled  "A  Contribution  to  the 
Study  of  the  Insect  Fauna  of  Human  Excrement  (with  special  refer- 
ence to  the  spread  of  typhoid  fever  by  flies) ,"  published  in  the  Pro- 
ceedings of  the  Washington  Academy  of  Sciences,  Volume  II,  pages 
541-604,  December  28,  1900,  he  showed  that  98.8  per  cent  of  the  whole 
number  of  insects  captured  in  houses  throughout  the  whole  country 
under  the  conditions  indicated  above  were  Musca  domestica,  the 
typhoid  or  house  fly.  He  showed  further  that  this  fly,  while  breeding 
most  numerously  in  horse  stables,  is  also  attracted  to  human  excre- 
ment and  will  breed  in  this  substance.  It  was  shown  that  in  towns 
where  the  box  privy  was  still  in  existence  the  house  fly  is  attracted  to 
the  excrement,  and,  further,  that  it  is  so  attracted  in  the  filthy  regions 
of  a  city  where  sanitary  supervision  is  lax  and  where  in  low  alleys 
and  corners  and  in  vacant  lots  excrement  is  deposited  by  dirty  people. 
He  stated  that  he  had  seen  excrement  which  had  been  deposited  over- 
night in  an  alleyway  in  South  Washington  swarming  with  flies  under 
the  bright  sunlight  of  a  June  morning  (temperature  92°  F.),  and  that 
within  30  feet  of  these  deposits  ^vere  the  open  windows  and  doors  of 
the  kitchens  of  two  houses  kept  by  poor  people,  these  two  houses 
being  only  elements  in  a  long  row.  The  following  paragraph  is 
quoted  from  the  paper  just  cited: 

"  Now.  when  we  consider  the  prevalence  of  typhoid  fever  and  that 
virulent  typhoid  bacilli  may  occur  in  the  excrement  of  an  individual 
for  some  time  before  the  disease  is  recognized  in  him,  and  that  the 
same  virulent  germs  may  be  found  in  the  excrement  for  a  long  time 
after  the  apparent  recovery  of  a  patient,  the  wonder  is  not  that  ty- 
phoid is  so  prevalent  but  that  it  does  not  prevail  to  a  much  greater 


26  LOSS   THROUGH   INSECTS  THAT   CARRY   DISEASE. 

extent.  Box  privies  should  be  abolished  in  every  community.  The 
depositing  of  excrement  in  the  open  within  town  or  city  limits  should 
be  considered  a  punishable  misdemeanor  in  communities  which  have 
not  already  such  regulations,  and  it  should  be  enforced  more  rigor- 
ously in  towns  in  which  it  is  already  a  rule.  Such  offenses  are  gener- 
ally committed  after  dark,  and  it  is  often  difficult  or  even  impossible 
to  trace  the  offender ;  therefore,  the  regulation  should  be  carried  even 
further  and  require  the  first  responsible  person  wTho  notices  the  de- 
posit to  immediately  inform  the  police,  so  that  it  may  be  removed  or 
covered  up.  Dead  animals  are  so  reported ;  but  human  excrement  is 
much  more  dangerous.  Boards  of  health  in  all  communities  should 
look  after  the  proper  treatment  or  disposal  of  horse  manure,  primarily 
in  order  to  reduce  the  number  of  house  flies  to  a  minimum,  and  all 
regulations  regarding  the  disposal  of  garbage  and  foul  matter  should 
be  made  more  stringent  and  should  be  more  stringently  enforced." 

In  the  opening  sentence  of  the  paragraph  just  quoted  attention  was 
called  to  the  activity  of  bacilli  in  excreta  passed  by  individuals  after 
apparent  recovery  from  typhoid.  Since  the  paper  in  question  was 
published,  more  especial  attention  has  been  drawn  by  medical  men 
to  this  point,  and  it  has  been  shown  that  individuals  who  are  chronic 
spreaders  of  the  typhoid  germs  are  much  more  abundant  than  was 
formerly  supposed.  Dr.  George  A.  Soper  recently  discovered  a  strik- 
ing case  of  this  kind  in  the  person  of  a  cook  employed  successively 
by  several  families  in  the  vicinity  of  New  York  City,  with  the  result 
that  several  cases  of  typhoid  occurred  in  each  of  these  families.  In 
a  paper  by  Doctor  Davids  and  Professor  Walker,  read  before  the 
Royal  Sanitary  Institute  of  London  during  the  present  season,  the 
history  was  given  of  four  personal  carriers  of  typhoid  who  had  com- 
municated the  disease  to  a  number  of  people.  These  four  carriers 
were  detected  in  one  city  within  a  few  months,  and  from  this  fact 
it  can  be  argued  with  justice  that  such  cases  are  comparatively  numer- 
ous. This  being  true,  the  presence  of  unguarded  miscellaneous 
human  excreta  deposited  in  city  suburbs,  in  vacant  lots,  and  in  low 
alleyways  intensifies  to  a  very  marked  degree  the  danger  that  the  food 
will  become  contaminated  with  typhoid  bacilli  by  means  of  the  ty- 
phoid or  house  fly.  It  is  known,  too,  that  the  urine  of  persons  who 
have  suffered  from  typhoid  fever  often  contains  active  typhoid  bacilli 
for  several  weeks  after  the  patients  have  recovered ;  consequently  this 
also  is  a  source  of  danger. 

The  importance  of  the  typhoid  fly  as  a  carrier  of  the  disease  in  army 
camps,  as  shown  in  the  Spanish  war  and  in  the  Boer  war  and  in  the 
camps  of  great  armies  of  laborers  engaged  in  gigantic  enterprises  like 
the  digging  of  the  Panama  canal,  is  obvious,  but  what  has  just  been 
stated  indicates  that  even  under  city  conditions  the  influence  of  this 
fly  in  the  spread  of  this  disease  has  been  greatly  underestimated.  It 
is  not  claimed  that  under  city  conditions  the  house  fly  becomes  by  this 
argument  a  prime  factor  in  the  transfer  of  the  disease,  but  it  must 
obviously  take  a  much  higher  relative  rank  among  typhoid  conveyers 


THE    TYPHOID    FLY,    OR    HOUSE   FLY.  27 

than  it  has  hitherto  assumed.  Perhaps  even  under  city  condition- 
it  must  assume  third  rank— next  to  'water  and  milk.° 

It  is  not  alone  as  a  carrier  of  typhoid  that  this  fly  is  to  be  feared. 
In  the  same  way  it  may  carry  nearly  all  the  intestinal  diseases.  It  is 
a  prime  agent  in  the  spreading  of  summer  dysentery,  and  in  this  way 
is  unquestionably  responsible  for  the  death  of  many  children  in  sum- 
mer. One  of  the  earliest  accurate  scientific  studies  of  the  agency  of 
insects  in  the  transfer  of  human  disease  was  in  regard  to  flies  as 
spreaders  of  cholera.  The  belief  in  this  agency  long  preceded  its 
actual  proof.  Dr.  G.  E.  Nicholas,  in  the  London  Lancet,  Volume  II, 
1873,  page  72-1,  is  quoted  by  Xuttall  as  writing  as  follows  regarding 
the  cholera  prevailing  at  Malta  in  1849 :  "  My  first  impression  of  the 
possibility  of  the  transfer  of  the  disease  by  flies  was  derived  from  the 
observation  of  the  manner  in  which  these  voracious  creatures,  present 
in  great  numbers,  and  having  equal  access  to  the  dejections  and  food 
of  patients,  gorged  themselves  indiscriminately  and  then  disgorged 
themselves  on  the  food  and  drinking  utensils.  In  1850  the  Superb, 
in  common  with  the  rest  of  the  Mediterranean  squadron,  was  at  sea 
for  nearly  six  months;  during  the  greater  part  of  the  time  she  had 
cholera  on  board.  On  putting  to  sea,  the  flies  were  in  great  force; 
but  after  a  time  the  flies  gradually  disappeared,  and  the  epidemic 
slowly  subsided.  On  going  into  Malta  Harbor,  but  without  com- 
municating with  the  shore,  the  flies  returned  in  greater  force,  and  the 
cholera  also  with  increased  violence.  After  more  cruising  at  sea,  the 
flies  disappeared  gradually  with  the  subsidence  of  the  disease.'' 

Accurate  scientific  bacteriological  observations  by  Tizzoni  and 
Cattani  in  1886  showed  definitely  active  cholera  organisms  in  the 
dejecta  of  flies  caught  in  the  cholera  wards  in  Bologna,  Italy.  These 
observations  were  subsequently  verified  and  extended  by  Simonds, 
Offelmann,  Macrae,  and  others. 

With  tropical  dysentery  and  other  enteric  diseases  practically  the 
same  conditions  exist.  In  a  report  by  Daniel  D.  Jackson  to  the 
committee  on  pollution,  of  the  Merchants'  Association  in  New  York, 
published  in  December,  1907,  the  results  of  numerous  observations 
upon  the  relation  of  flies  to  intestinal  diseases  are  published,  and  the 
relation  of  deaths  from  intestinal  diseases  in  New  York  City  to  the 

aDr.  John  R.  Mohler,  of  the  Bureau  of  Animal  Industry,  U.  S.  Department 
of  Agriculture,  informs  the  writer  that  investigations  made  in  his  office  show 
that  typhoid  bacilli  will  live  in  butter  under  common  market  conditions  for  151 
days  and  still  be  able  to  grow  when  transferred  to  suitable  conditions.  In 
milk  under  market  conditions  they  retain  active  motility  for  20  days,  after 
which  time  there  is  a  gradual  lessening  in  numbers  until,  on  the  forty-third  day 
of  the  test,  they  disappear  from  view.  At  certain  seasons,  of  the  year  large  num- 
bers of  flies  collect  upon  the  vats  in  which  milk  and  cream  are  being  stored 
in  dairies  and  creameries.  Many  of  the  flies  fall  in,  their  bodies  being  strained 
out  when  the  cream  is  sent  to  the  churn.  If  any  of  these  flies  carry  typhoid 
bacilli  these  are  washed  off  by  the  milk  and  remain  in  the  butter  or  cheese 
made  from  it.  Thus  the  eating  of  butter  contaminated  in  this  way  may  account 
for  very  many  cases  of  typhoid  fever  the  cause  of  which  can  not  be  otherwise 
traced. 


28  LOSS   THROUGH    INSECTS   THAT    CARRY   DISEASE. 

activity  and  prevalence  of  the  common  house  fly  is  shown  not  only 
by  repeated  observations  but  also  by  an  interesting  plotting  of  the 
curve  of  abundance  of  flies  in  comparison  with  the  plotted  curve  of 
abundance  of  deaths  from  intestinal  diseases,  indicating  that  the 
greatest  number  of  flies  occurred  in  the  weeks  ending  July  27  and 
August  3 ;  also,  that  the  deaths  from  intestinal  diseases  rose  above 
the  normal  at  the  same  time  at  which  flies  became  prevalent,  culmi- 
nated at  the  same  high  point,  and  fell  off  with  slight  lag  at  the 
time  of  the  gradual  falling  off  of  the  prevalence  of  the  insects. 

Similar  studies  have  been  carried  on  during  the  summer  of  1908 
in  the  city  of  Washington ,  and  the  curve  of  typhoid-fly  abundance 
for  the  whole  city,  as  well  as  that  for  a  district  comprising  eight  city 
squares  in  which  intensive  studies  have  been  made  both  of  flies  and 
of  disease,  will  be  plotted  at  the  close  of  the  season.  At  the  time 
of  present  writing  this  work  has.  not  been  completed. 

The  typhoid  fly  also  possesses  importance  as  a  disseminator  of  the 
bacilli  of  tuberculosis.  In  a  paper  by  Dr.  Frederick  T.  Lord,  of 
Boston,  reprinted  from  the  Boston  Medical  and  Surgical  Journal  for 
December  15,  1904,  pages  651-654,  the  following  conclusions  are 
reached : 

"  1.  Flies  may  ingest  tubercular  sputum  and  excrete  tubercle  ba- 
cilli, the  virulence  of  which  may  last  for  at  least  fifteen  day-. 

"  2.  The  danger  of  human  infection  from  tubercular  flyspecks  is 
by  the  ingestion  of  the  specks  on  food.  Spontaneous  liberation  of 
tubercle  bacilli  from  flyspecks  is  unlikely.  If  mechanically  dis- 
turbed, infection  of  the  surrounding  air  may  occur. 

"As  a  corollary  to  these  conclusions,  it  is  suggested  that — 

"  3.  Tubercular  material  (sputum,  pus  from  discharging  sinuses. 
fecal  matter  from  patients  with  intestinal  tuberculosis,  etc.)  should 
be  carefully  protected  from  flies,  lest  they  act  as  disseminators  of  the 
tubercle  bacilli. 

"  4.  During  the  fly  season  greater  attention  should  be  paid  to  the 
screening  of  rooms  and  hospital  wards  containing  patients  with 
tuberculosis  and  laboratories  where  tubercular  material  is  examined. 

"  5.  As  these  precautions  would  not  eliminate  fly  infection  by 
patients  at  large,  foodstuffs  should  be  protected  from  flies  which  may 
already  have  ingested  tubercular  material." 

From  all  these  facts  it  appears  that  the  most  important  part  played 
by  the  typhoid  fly  or  house  fly  in  the  human  economy  is  to  carry 
bacteria  from  one  place  to  another.  The  following  table  and  com- 
ments are  taken  from  Bulletin  Xo.  51  (April,  1908).  of  the  Storrs 
Agricultural  Experiment  Station,  Storrs,  Conn.,  entitled  "  Sources  of 
Bacteria  in  Milk."  bv  W.  M.  Esten  and  C.  J.  Mason : 


THE   TYPHOID   FLY,    OR   HOUSE   FLY. 


29 


Table  III. — Sources  of  bacteria  from  Jli 


1907. 
July  27 

July  27 

Aug.  6 

Aug.14 

Aug.  14 

Sept.  4 

Sept.21 

Sept. 21 

Sept.27 

Aug.  20 


Source. 


(a)  1  fly,  bacteriological 
laboratory 

(b)  1  fly.  bacteriological 
laboratory 

(c)  19  cow-stable  flies 

Average  per  fly 

(d)  94  swill-barrel  flies 

Average  per  fly 

(c)  144  pigpen  flies 

Average  per  fly 

(/)  18  swill-barrel  flies 

Average  per  fly 

(g)  30  dwelling-house  flies. 

Average  per  fly 

(h)  26 dwelling-house  flies. 

Average  per  fly 

(i)  110  dwelling-house  flies. 

Average  per  fly 

(j)  1  large  bluebottle 
blowfly 


Total        Total  acid 
number.      bacteria. 


3,150 

550 

7. 980,  000 

420, 000 

155, 000, 000 

1,660,000 

133, 000,  000 

923,000 

118,800,000 

6, 600, 000 

1, 425, 000 

47,580 

22, 880, 000 

880,000 

35,500,000 

322, 700 

308, 700 


220 

11 

8,950 

95 

2,110 

18, 

10, 480 

2, 182, 

125, 

4; 

22, 596 

869 

13,  670 

124; 


250 

100 
,000 
,600 
,000 
,300 
,000 
,700 
,000 
,000 
,000 

167 
,000 
,000 
,000 

200 


Rapid 
liquefy- 
ing bac- 
teria. 


(«) 


600 

0 
0 
0 
0 
0 

100,000 
700 
0 
0 
0 
0 

120,000 
4,600 

840,000 
80,300 


Slow 
liquefy- 
ing bac- 
teria. 


100 

0 

20,000 

1,000 

0 

0 

266,000 

1,150 


4,  320, 000 

46,000 

933,000 

6,500 

14,500.000   10,480,000 
804.000  I      582,000 


Bacterium 

lactis 

acidi. 

Group  A. 

Class  1. 


Coli-sero- 

genes. 
Group  A. 
Class  2. 


12,500 

417 

34,000 

1,300 

125,000 

1.100 


Total  average  of  414  flies . .      1 ,  222, 570 
Average  per  cent  of  414 
flies 

Average   per   fly    of    256  j 

flies,    experiments    (d),  ! 

(e),and(/) 3,061,000 

Average  per  cent  of    256 

flies,    experiments    (d),  < 

(0,and  (/) 


367, 300 

7,830 

30 

6 

765,000 

230 

„ 

73,500 


268, 700 
8 


211,500 

7 


4, 630, 000 
49,300 

1,176,000 

12,200 

30,000,000 

1,600,000 


;53,  800 
18 


a  2,200  mold  spores. 

"  From  the  above  table  the  bacterial  population  of  414  flies  is  pretty 
well  represented.  The  domestic  fly  is  passing  from  a  disgusting  nui- 
sance and  troublesome  pest  to  a  reputation  of  being  a  dangerous 
enemy  to  human  health.  A  species  of  mosquito  has  been  demon- 
strated to  be  the  cause  of  the  spread  of  malaria.  Another  kind  of 
mosquito  is  the  cause  of  yellow  fever,  and  now  the  house  fly  is  con- 
sidered an  agency  in  the  distribution  of  typhoid  fever,  summer  com- 
plaint, cholera  infantum,  etc. 

"  The  numbers  of  bacteria  on  a  single  fly  may  range  all  the  way 
from  550  to  6,600,000.  Early  in  the  fly  season  the  numbers  of  bac- 
teria on  flies  are  comparatively  small,  while  later  the  numbers  are 
comparatively  very  large.  The  place  where  flies  live  also  determines 
largely  the  numbers  that  they  carry.  The  average  for  the  414  flies 
was  about  one  and  one-fourth  million  bacteria  on  each.  It  hardly 
seems  possible  for  so  small  a  bit  of  life  to  carry  so  large  a  number  of 
organisms.  The  method  of  the  experiment  was  to  catch  the  flies  from 
the  several  sources  by  means  of  a  sterile  fly  net,  introduce  them  into 
a  sterile  bottle,  and  pour  into  the  bottle  a  known  quantity  of  steril- 
ized water,  then  shake  the  bottle  to  wash  the  bacteria  from  their 
bodies,  to  simulate  the  number  of  organisms  that  would  come  from  a 
fly  in  falling  into  a  lot  of  milk.     In  experiments  '  dj  i  <?,'  and  '  / ' 


30  LOSS   THROUGH    INSECTS   THAT   CARRY   DISEASE. 

the  bacteria  were  analyzed  into  four  groups.  The  objectionable  class, 
coli-cerogenes  type,  was  two  and  one-half  times  as  abundant  as  the 
favorable  acid  type.  If  these  flies  stayed  in  the  pigpen  vicinity  there 
would  be  less  objection  to  the  flies  and  the  kinds  of  organisms  they 
carry,  but  the  fly  is  a  migratory  insect  and  it  visits  everything  '  under 
the  sun/  It  is  almost  impossible  to  keep  it  out  of  our  kitchens,  din- 
ing rooms,  cow  stables,  and  milk  rooms.  The  only  remedy  for  this 
rather  serious  condition  of  things  is,  remove  the  pigpen  as  far  as  pos- 
sible from  the  dairy  and  dwelling  house.  Extreme  care  should  be 
taken  in  keeping  flies  out  of  the  cow  stable,  milk  rooms,  and  dwell- 
ings. Flies  walking  over  our  food  are  the  cause  of  one  of  the  worst 
contaminations  that  could  occur  from  the  standpoint  of  cleanliness 
and  the  danger  of  distributing  disease  germs." 

The  danger  of  the  typhoid  or  house  fly  in  the  carriage  of  disease 
has  thus  been  abundantly  demonstrated.  Further  than  this,  it  is  an 
intolerable  nuisance.  With  mosquitoes  it  necessitates  an  annual  out- 
lay for  window  and  door  screens  in  the  United  States  of  not  less  than 
ten  millions  of  dollars.  As  a  carrier  of  disease  it  causes  a  loss  of 
many  millions  of  dollars  annually.  Dr.  G.  N.  Kober,  in  a  paper  pre- 
pared for  the  Governors'  Conference  on  the  Conservation  of  Natural 
Resources,  held  at  the  White  House  in  May,  1908,  entitled  "  The  Con- 
servation of  Life  and  Health  by  Improved  Water  Supply,"  presented 
figures  showing  that  the  decrease  in  the  vital  assets  of  the  country 
through  typhoid  fever  in  a  single  }Tear  is  more  than  $350,000,000. 
The  house  fly,  as  an  important  agent  in  the  spread  of  this  disease,  is 
responsible  for  a  very  considerable  portion  of  this  decrease  in  vital 
assets.  As  an  agency  in  the  spread  of  other  intestinal  diseases,  this 
sum  must  be  greatly  increased,  and  }^et  it  is  allowed  to  breed  unre- 
stricted all  over  the  United  States;  it  is  allowed  to  enter  freely  the 
houses  of  the  great  majority  of  our  people;  it  is  allowed  to  spread 
bacteria  freely  over  our  food  supplies  in  the  markets  and  in  the 
kitchens  and  dining  rooms  of  private  houses,  and,  to  use  the  happy 
phraseology  of  Dr.  Theobald  Smith,  "  when  we  go  into  public  restau- 
rants in  midsummer  Ave  are  compelled  to  fight  for  our  food  with  the 
myriads  of  house  flies  which  we  find  there  alert,  persistent,  and 
invincible." 

Even  if  the  typhoid  or  house  fly  were  a  creature  difficult  to  de- 
stroy, the  general  failure  on  the  part  of  communities  to  make  any 
efforts  whatever  to  reduce  its  numbers  could  properly  be  termed 
criminal  neglect;  but  since,  as  will  be  shown,  it  is  comparatively  an 
easy  matter  to  do  away  with  the  plague  of  flies,  this  neglect  becomes 
an  evidence  of  ignorance  or  of  a  carelessness  in  regard  to  disease- 
producing  filth  which  to  the  informed  mind  constitutes  a  serious  blot 
on  civilized  methods  of  life. 


THE   TYPHOID   FLY,    OR   HOUSE   FLY.  31 

Strange  as  it  may  seem,  an  exhaustive  study  of  the  conditions 
which  produce  house  flies  in  numbers  has  never  been  made.  The 
life  history  of  the  insect  in  general  was,  down  to  1873,  mentioned  in 
only  three  European  works  and  few  exact  facts  were  given.  In  1873 
Dr.  A..S.  Packard,  then  of  Salem,  Mass.,  studied  the  transformations 
of  the  insect  and  gave  descriptions  of  all  stages,  showing  that  the 
growth  of  a  generation  from  the  egg  state  to  the  adult  occupies  from 
10  to  14  days. 

In  1895  the  writer  traced  the  life  history  in  question,  indicating 
that  120  eggs  are  laid  by  a  single  female,  and  that  in  Washington, 
in  midsummer,  a  generation  is  produced  every  10  days.  Although 
numerous  substances  were  experimented  with,  he  was  able  to  breed 
the  fly  only  in  horse  manure.  Later  investigations  indicated  that  the 
fly  will  breed  in  human  excrement  and  in  other  fermenting  vegetable 
and  animal  material,  but  that  the  vast  majority  of  the  flies  that 
infest  dwelling  houses,  both  in  cities  and  on  farms,  come  from  horse 
manure. 

In  1907  careful  investigations  carried  on  in  the  city  of  Liverpool 
by  Robert  Xewstead,  lecturer  in  economic  entomology  and  para- 
sitology in  the  School  of  Tropical  Medicine  of  the  University  of 
Liverpool,  indicated  that  the  chief  breeding  places  of  the  house  fly 
in  that  city  should  be  classified  under  the  following  heads : 

(1)  Middensteads  (places  where  dung  is  stored)  containing  horse 
manure  only. 

(2)  Middensteads  containing  spent  hops. 

(3)  Ash  pits  containing  fermenting  materials. 

He  found  that  the  dung  heaps  of  stables  containing  horse  manure 
only  were  the  chief  breeding  places.  Where  horse  and  cow  manures 
were  mixed  the  flies  bred  less  numerously,  and  in  barnyards  where 
fowls  were  kept  and  allowed  freedom  relatively  few  of  the  house 
flies  were  found.  Only  one  midden  containing  warm  spent  hops  was 
inspected,  and  this  was  found  to  be  as  badly  infested  as  any  of  the 
stable  middens.  A  great  deal  of  time  was  given  to  the  inspection  of 
ash  pits,  and  it  was  found  that  wherever  fermentation  had  taken 
place  and  artificial  heat  had  been  thus  produced,  such  places  were 
infested  with  house-fly  larva?  and  pupa?,  often  to  the  same  alarming 
extent  as  in  stable  manure.  Such  ash  pits  as  these  almost  invariably 
contained  large  quantities  of  old  bedding  or  straw  and  paper,  paper 
mixed  with  human  excreta,  or  old  rags,  manure  from  rabbit  hutches, 
etc.,  or  a  mixture  of  all  these.  About  25  per  cent  of  the  ash  pits 
examined  were  thus  infested,  and  house  flies  were  found  breeding 
in  smaller  numbers  in  ash  pits  in  which  no  heat  had  been  engendered 
by  fermentation.  The  house  fly  was  also  found  breeding  by  Mr. 
Newstead  in  certain  temporary  breeding  places,  such  as  collections 


32  LOSS   THROUGH    IXSKCTS    THAI     CABBY    DISEASE. 

of  fermenting  vegetable  refuse,  accumulations  of  manure  at  the 
wharves,  and  in  bedding  in  poultry  pens. 

Still  more  recent  investigations  were  carried  on  during  1908  by 
Prof.  S,  A.  Forbes,  State  entomologist  of  Illinois,  who  has  reared  it 
in  large  numbers  from  the  contents  of  paunches  of  slaughtered  cattle, 
from  refuse  hog  hairs,  from  tallow  vats,  from  carcasses  of  various 
animals,  miscellaneous  garbage,  and  so  on. 

All  this  means  that  if  we  allow  the  accumulation  of  filth  we  will 
have  house  flies,  and  if  we  do  not  allow  it  to  accumulate  we  will  have 
no  house  flies.  With  the  careful  collection  of  garbage  in  cans  and 
the  removal  of  the  contents  at  more  frequent  intervals  than  10  days, 
and  with  the  proper  regulation  of  abattoirs,  and  more  particularly 
with  the  proper  regulation  of  stables  in  which  horses  are  kept,  the 
typhoid  fly  will  become  a  rare  species.  It  will  not  be  necessary  to 
treat  horse  manure  with  chlorid  of  lime  or  with  kerosene  or  with  a 
solution  of  Paris  green  or  arsenate  of  lead,  if  stable  men  are  required 
to  place  the  manure  daily  in  a  properly  covered  receptacle  and  if  it 
is  carried  away  once  a  week. 

The  orders  of  the  health  department  of  the  District  of  Columbia, 
published  May  3.  1900,  if  carried  out  will  be  very  effective.  These 
orders  may  be  briefly  condensed  as  follows: 

All  stalls  in  which  animals  are  kept  shall  have  the  surface  of  the 
ground  covered  with  a  water-tight  floor.  Every  person  occupying 
a  building  where  domestic  animals  are  kept  shall  maintain,  in  con- 
nection therewith,  a  bin  or  pit  for  the  reception  of  manure,  and  pend- 
ing the  removal  from  the  premises  of  the  manure  from  the  animal 
or  animals  shall  place  such  manure  in  said  bin  or  pit.  This  bin  shall 
be  so  constructed  as  to  exclude  rain  water,  and  shall  in  all  other  re- 
spects be  water-tight,  except  as  it  may  be  connected  with  the  public 
sewer.  It  shall  be  provided  with  a  suitable  cover  and  constructed 
so  as  to  prevent  the  ingress  and  egress  of  flies.  No  person  owning 
a  stable  shall  keep  any  manure  or  permit  any  manure  to  be  kept  in 
or  upon  any  portion  of  the  premises  other  than  the  bin  or  pit  de- 
scribed, nor  shall  he  allow  any  such  bin  or  pit  to  be  overfilled  or 
needlessly  uncovered.  Horse  manure  may  be  kept  tightly  rammed 
into  well-covered  barrels  for  the  purpose  of  removal  in  such  barrels. 
Every  person  keeping  manure  in  any  of  the  more  densely  populated 
parts  of  the  District  shall  cause  all  such  manure  to  be  removed  from 
the  premises  at  least  twice  every  week  between  June  1  and  October  31, 
and  at  least  once  every  week  between  November  1  and  May  31  of 
the  following  year.  Xo  person  shall  remove  or  transport  any  manure 
over  any  public  highway  in  any  of  the  more  densely  populated  parts 
of  the  District  except  in  a  tight  vehicle,  which,  if  not  inclosed,  must 
be  effectually  covered  with  canvas,  so  as  to  prevent  the  manure  from 
being  dropped.     Xo  person  shall  deposit  manure  removed  from  the 


THE   TYPHOID   FLY,    OR   HOUSE   FLY.  33 

bins  or  pits  within  any  of  the  more  densely  populated  parts  of  the 
District  without  a  permit  from  the  health  officer.  Any  person 
violating  any  of  these  provisions  shall,  upon  conviction  thereof,  be 
punished  by  a  fine  of  not  more  than  $40  for  each  offense. 

In  addition  to  this  excellent  ordinance,  others  have  been  issued 
from  the  health  department  of  the  District  of  Columbia  which  provide 
against  the  contamination  of  exposed  food  by  flies  and  by  dust.  The 
ordinances  are  excellently  worded  so  as  to  cover  all  possible  cases. 
They  provide  for  the  registration  of  all  stores,  markets,  cafes,  lunch 
rooms,  or  of  any  other  place  where  food  or  beverage  is  manufactured 
or  prepared  for  sale,  stored  for  sale,  offered  for  sale,  or  sold,  in  order 
to  facilitate  inspection,  and  still  more  recent  ordinances  provide  for 
the  registration  of  stables.  An  excellent  campaign  was  begun  during 
the  summer  of  1908  against  insanitary  lunch  rooms  and  restaurants. 
A  number  of  cases  were  prosecuted,  but  conviction  was  found  to  be 
difficult. 

For  one  reason  or  another,  the  chief  reason  being  the  lack  of  a 
sufficient  force  of  inspectors  under  the  control  of  the  health  officers, 
the  ordinance  in  regard  to  stables  has  not  been  carried  out  with  that  t 
perfection  which  the  situation  demands.  In  the  summer  of  1896,  the 
health  officer  of  the  District,  Dr.  W.  C.  Woodward,  designated  a 
region  in  Washington  bounded  by  Pennsylvania  avenue,  Sixth  street, 
Fifteenth  street,  and  the  Potomac  River,  which  was  to  be  watched 
by  assistants  of  the  writer.  Twenty- four  stables  were  located  in  this 
region  and  were  visited  weekly  by  two  assistants  chosen  for  the  pur- 
pose. The  result  was  that  on  the  whole  the  manure  was  well  looked 
after  and  the  number  of  flies  in  the  region  in  question  was  very  con- 
siderably reduced  during  the  time  of  inspection. 

Were  simple  inspection  of  stables  all  that  is  needed,  a  force  of  four 
inspectors,  specially  detailed  for  this  work,  could  cover  the  District 
of  Columbia,  examining  every  stable,  after  they  were  once  located  and 
mapped,  once  a  week.  The  average  salary  of  an  inspector  is  $1,147, 
so  that  the  total  expense  for  the  first  year  would  be  something  like 
$4,500.  But  the  inspectors'  service  is  complicated  by  the  matter  of 
prosecution.  Much  of  the  time  of  inspectors  would  be  taken  in  the 
prosecution  of  the  owners  of  neglected  premises.  Moreover,  the  health 
officer  has  found  during  the  summer  of  1908,  in  his  prosecution  of  the 
owners  or  managers  of  insanitary  restaurants,  that  his  inspectors  were 
practically  sworn  out  of  court  by  the  multiplicity  of  opposing  evi- 
dence. This  means  that  it  will  be  necessary  in  such  cases  to  send  two 
inspectors  together  in  all  cases,  so  that  the  testimony  of  one  may  be 
supported  by  the  testimony  of  the  other.  This,  perhaps,  would  double 
the  number  of  necessary  inspectors,  making  the  expense  of  the  service 
something  over  $9,000.     It  is  reasonably  safe  to  state,  however,  that 


34  LOSS   THROUGH    INSECTS   THAT    CARRY    DISEASE. 

with  such  an  expense  for  competent  service,  or  perhaps  with  a  slightly 
added  expense,  the  typhoid  fly  could  be  largely  eliminated  as  an  ele- 
ment in  the  transfer  of  disease  in  the  District  of  Columbia,  and  the 
difficulty  which  the  authorities  have  had  in  locating  the  cause  of  a 
very  considerable  proportion  of  the  cases  of  typhoid  in  the  District 
for  the  past  two  or  three  years  indicates  plainly  to  the  mind  of  the 
writer  that  the  typhoid  fly  is  a  much  more  important  element  than 
has  been  supposed.  It  is  a  comforting  although  comparatively  insig 
nificant  fact  and  a  matter  of  common  observation  that  in  certain 
sections  of  the  city  the  typhoid  fly  has  been  much  less  numerous  dur- 
ing the  past  summer  than  in  previous  years.  The  writer  is  inclined 
to  attribute  this  to  the  gradual  disappearance  of  horse  stables  in 
such  sections,  brought  about  by  the  rapidly  increasing  use  of  motor 
vehicles. 

A  significant  paragraph  in  Mr.  Xewstead's  Liverpool  report,  re- 
ferred to  above,  contains  the  following  words :  "  The  most  strenuous 
efforts  should  be  made  to  prevent  children  defecating  in  the  courts 
and  passages ;  or  that  the  parents  should  be  compelled  to  remove  such 
matter  immediately ;  and  that  defecation  in  stable  middens  should  be 
strictly  forbidden.  The  danger  lies  in  the  overwhelming  attraction 
which  such  fecal  matter  has  for  house  flies,  which  later  may  come  into 
direct  contact  with  man  or  his  foodstuffs.  They  may,  as  Veeder  puts 
it, '  In  a  very  few  minutes  *  *  *  load  themselves  with  dejections 
from  a  typhoid  or  dysenteric  patient,  not  as  yet  sick  enough  to  be  in 
hospital  or  under  observation,  and  carry  the  poison  so  taken  up  into 
the  very  midst  of  the  food  and  water  ready  for  use  at  the  next  meal. 
There  is  no  long,  roundabout  process  involved.' " 

The  writer  has  already  referred  to  this  general  subject  in  his  re- 
marks on  the  depositing  of  excrement  in  the  open  within  town  or  city 
limits,  but  Newstead's  specific  reference  to  children  reminds  one  that 
in  the  tenement  districts  of  the  older  great  cities  of  England  and  other 
parts  of  Europe  there  occur  opportunities  for  transfer  of  disease 
which,  while  probably  less  numerous  in  the  newer  cities  of  the  United 
States,  nevertheless  must  still  exist  and  be  a  constant  danger. 

We  have  thus  shown  that  the  typhoid  or  house  fly  is  a  general  and 
common  carrier  of  pathogenic  bacteria.  It  may  carry  typhoid  fever, 
Asiatic  cholera,  dysentery,  cholera  morbus,  and  other  intestinal  dis- 
eases ;  it  may  carry  the  bacilli  of  tuberculosis  and  certain  eye  diseases ; 
it  is  everywhere  present,  and  it  is  disposed  of  with  comparative  ease. 
It  is  the  duty  of  every  individual  to  guard  so  far  as  possible  against 
the  occurrence  of  flies  upon  his  premises.  It  is  the  duty  of  every  com- 
munity, through  its  board  of  health,  to  spend  money  in  the  warfare 
against  this  enemy  of  mankind.  This  duty  is  as  pronounced  as  though 
the  community  were  attacked  by  bands  of  ravenous  wolves. 


THE   TYPHOID   FLY,    OR   HOUSE   FLY.  35 

As  a  matter  of  fact,  large  sums  of  money  are  spent  annually  in  the 
protection  of  property  in  the  United  States.  Large  sums  of  money 
are  spent  also  in  health  matters;  but  the  expenditure  for  protection 
from  flies  is  very  small  and  is  misdirected.  There  is  much  justifica- 
tion for  the  following  criticism  published  editorially  in  the  Journal 
of  the  American  Medical  Association  for  August  22,  1908,  under  the 
caption,  "  National  Farm  Commission  and  Rural  Sanitation :" 

"The  President  calls  attention  to  the  fact  that  all  efforts  to  aid  the 
farmers  have  hitherto  been  directed  to  improving  their  material 
welfare,  while  the  man  himself  and  his  family  have  been  neglected. 
Nowhere  is  this  more  marked  than  in  the  attitude  of  the  General 
Government  in  matters  relating  to  sanitation.  It  is  a  trite  saying 
that  whereas  the  Government,  through  the  Department  of  Agricul- 
ture, aids  the  farmer  generously  in  caring  for  the  health  of  his  hogs, 
sheep,  etc.,  it  does  nothing  for  his  own  health.  The  Government 
issues  notices  to  the  farmer  of  the  injury  done  to  his  crops  by  the 
cotton-boll  weevil  and  the  potato  bugs  and  how  to  combat  them,  but 
the  injury  the  mosquito  does  in  spreading  malaria  to  the  people  who 
pick  the  cotton  and  hoe  the  potatoes  is  not  impressed  on  him.  The 
fact  that  horseflies  may  carry  anthrax  to  his  cattle  is  dealt  with  at 
considerable  length,  but  the  diseases  which  the  house  fly  spreads  to 
the  milk  and  to  the  farmer's  family  attract  practically  no  attention. 
How  to  build  a  hogpen  or  a  sanitary  barn  is  the  subject  of  a  number 
of  government  publications,  but  how  to  build  a  sanitary  privy  which 
will  prevent  the  spread  of  typhoid,  hook  worm,  and  many  other  dis- 
eases is  regarded  as  of  strictly  local  interest." 

But  this  criticism  is  not  entirely  justified,  since  there  was  published 
by  the  Bureau  of  Entomology  of  the  United  States  Department  of 
Agriculture,  in  1900,  a  Farmers'  Bulletin,  entitled  "  How  Insects 
Affect  Health  in  Rural  Districts,"  a  in  which  all  of  these  points  men- 
tioned by  the  editor  of  the  Journal  of  the  American  Medical  Asso- 
ciation have  been  touched  upon,  and  at  the  date  of  present  writing 
192,000  copies  of  this  bulletin  have  been  distributed  among  the 
people.  Moreover,  a  number  of  years  ago  a  circular h  was  published 
on  the  subject  of  the  house  fly,  calling  attention  to  its  dangers  and 
giving  instructions  such  as  are  covered  in  a  general  way  in  this 
article,  and  some  18,000  copies  of  this  circular  have  also  been  dis- 
tributed. This  is  an  indication  that  the  General  Government  is  by 
no  means  blind  to  the  people's  needs  in  such  matters  as  we  have 
under  consideration,  but  further  work  should  be  done.  That  the 
English  Government  is  awaking  to  the  same  need  is  shown  by  the 
fact  that,  in  the  parliamentary  vote  of  the  present  year  in  aid  of 

a  Farmers'  Bulletin  No.  155. 

6  Circular  No.  35,  Bureau  of  Entomology,  1891,  afterwards  reissued  in  revised 
form  as  Circular  No.  71. 


3G  LOSS    THROUGH    INSECTS   THAT    CARRY    DISEASE. 

scientific  investigations  concerning  disease,  one  of  the  projects  sup- 
ported by  the  General  Government  was  the  investigation  of  Doctors 
Copeman  and  Nuttall  on  flies  as  carriers  of  disease. 

A  leading  editorial  in  an  afternoon  paper  of  the  city  of  Washing- 
ton, of  October  20,  1908,  bears  the  heading,  "  Typhoid  a  National 
Scourge,"  arguing  that  it  is  to-day  as  great  a  scourge  as  tuberculosis. 
The  editorial  writer  might  equally  well  have  used  the  heading  "  Ty- 
phoid a  National  Reproach,"  or  perhaps  even  "  Typhoid  a  National 
Crime,"  since  it  is  an  absolutely  preventable  disease.  And  as  for  the 
typhoid  fly,  that  a  creature  born  in  indescribable  filth  and  absolutely 
swarming  with  disease  germs  should  practically  be  invited  to  mul- 
tiply unchecked,  even  in  great  centers  of  population,  is  surely  nothing 
less  than  criminal. 

ENDEMIC  DISEASE  AS  AFFECTING  THE  PROGRESS  OF  NATIONS. 

In  referring  to  the  spread  of  malaria  in  Greece,  the  relation  of  this 
disease  to  the  rise  and  fall  of  national  power  has  been  touched  upon 
in  an  earlier  paragraph  of  this  bulletin  (p.  9).  The  subject  is  one  of 
the  widest  importance  and  deserves  a  more  extended  consideration. 

The  following  paragraphs  are  quoted  from  Ronald  Ross's  address 
on  Malaria  in  Greece,  delivered  before  the  Oxford  Medical  Society, 
November  29,  1906: 

"  Now,  what  must  be  the  effect  of  this  ubiquitous  and  everlasting 
incubus  of  disease  on  the  people  of  modern  Greece?  Remember  that 
the  malady  is  essentially  one  of  infancy  among  the  native  population. 
Infecting  the  child  one  or  two  years  after  birth,  it  persecutes  him 
until  puberty  with  a  long  succession  of  febrile  attacks,  accompanied 
by  much  splenomegaly  and  anaemia.  Imagine  the  effect  it  would 
produce  upon  our  own  children  here  in  Britain.  It  is  true  that  our 
children  suffer  from  many  complaints — scarlatina,  measles,  whoop- 
ing cough — but  these  are  of  brief  duration  and  transient.  But  now 
add  to  these,  in  imagination,  a  malady  which  lasts  for  years,  and  may 
sometimes  attack  every  child  in  a  village.  What  would  be  the 
effect  upon  our  population — especially  our  rural  population — upon 
their  numbers  and  upon  the  health  and  vigour  of  the  survivors?  It 
must  be  enormous  in  Greece.  People  often  seem  to  think  that  such  a 
plague  strengthens  a  race  by  killing  off  the  weaker  individuals ;  but 
this  view  rests  upon  the  unproven  assumption  that  it  is  really  the 
weaker  children  which  can  not  survive.  On  the  contrary,  experience 
seems  to  show  that  it  is  the  stronger  blood  which  suffers  most — the 
fair,  northern  blood  which  nature  attempts  constantly  to  pour  into 
the  southern  lands.  If  this  be  true,  the  effect  of  malaria  will  be 
constantly  to  resist  the  invigorating  influx  which  nature  has  provided ; 
and  there  are  many  facts  in  the  history  of  India,  Italy,  and  Africa 
which  could  be  brought  forward  in  support  of  this  hypothesis. 


ENDEMIC    DISEASE   AFFECTING  PROGRESS   OF    NATIONS.  37 

"  We  now  come  face  to  face  with  that  profoundly  interesting 
subject,  the  political,  economical,  and  historical  significance  of  this 
great  disease.  We  know  that  malaria  must  have  existed  in  Greece 
ever  since  the  time  of  Hippocrates,  about  400  B.  C.  What  effect 
has  it  had  on  the  life  of  the  country?  In  prehistoric  times  Greece 
was  certainly  peopled  by  successive  wave-  of  Aryan  invaders  from  the 
north — probably  a  fair-haired  people — who  made  it  what  it  became, 
who  conquered  Persia  and  Egypt,  and  who  created  the  sciences, 
arts,  and  philosophies  which  we  are  only  developing  further  to- 
day. That  race  reached  its  climax  of  development  at  the  time  of 
Pericles.  Those  great  and  beautiful  valleys  were  thickly  peopled 
by  a  civilization  which  in  some  ways  has  not  been  excelled. 
Everywhere  there  were  cities,  temples,  oracles,  arts,  philosophies, 
and  a  population  vigorous  and  well  trained  in  arms.  Lake  Kopais, 
now  almost  deserted,  was  surrounded  by  towns  whose  massive  works 
remain  to  this  day.  Suddenly,  however,  a  blight  fell  over  all.  Was 
it  due  to  internecine  conflict  or  to  foreign  conquest?  Scarcely:  for 
history  shows  that  war  burns  and  ravages,  but  does  not  annihilate. 
Thebes  was  thrice  destroyed,  but  thrice  rebuilt.  Or  was  it  due  to 
some  cause,  entering  furtively  and  gradually  sapping  away  the 
energies  of  the  race  by  attacking  the  rural  population,  by  slaying 
the  new-born  infant,  by  seizing  the  ri>ing  generation,  and  especially 
by  killing  out  the  fair-haired  descendant  of  the  original  settlers, 
leaving  behind  chiefly  the  more  immunised  and  darker  children  of 
their  captives,  won  by  the  sword  from  Asia  and  Africa  ?     *     *     * 

"  I  can  not  imagine  Lake  Kopais,  in  its  present  highly  malarious 
condition,  to  have  been  thickly  peopled  by  a  vigorous  race;  nor,  on 
looking  at  those  wonderful  figured  tombstones  at  Athens,  can  I 
imagine  that  the  healthy  and  powerful  people  represented  upon 
them  could  have  ever  passed  through  the  ana?mic  and  splenomegalous 
infancy  (to  coin  a  word)  caused  by  widespread  malaria.  Well,  I 
venture  only  to  suggest  the  hypothesis,  and  must  leave  it  to  scholars 
for  confirmation  or  rejection.  Of  one  thing  I  am  confident,  that 
causes  such  as  malaria,  dysentery,  and  intestinal  entozoa  must  have 
modified  history  to  a  much  greater  extent  than  we  conceive.  Our 
historians  and  economists  do  not  seem  even  to  have  considered  the 
matter.  It  is  true  that  they  speak  of  epidemic  diseases,  but  the 
endemic  diseases  are  really  those  of  the  greatest  importance.    *    *    * 

"  The  whole  life  of  Greece  must  suffer  from  this  weight,  which 
crushes  its  rural  energies.  Where  the  children  suffer  so  much,  how 
can  the  country  create  that  fresh  blood  which  keeps  a  nation  }Toung? 
But  for  a  hamlet  here  and  there,  those  famous  valleys  are  deserted. 
I  saw  from  a  spur  of  Helikon  the  sun  setting  upon  Parnassus,  Apollo 
sinking,  as  he  was  wont  to  do.  towards  his  own  fane  at  Delphi,  and 
pouring  a  flood  of  light  over  the  great  Kopaik  Plain.    But  it  seemed 


38  LOSS   THROUGH    INSECTS   THAT    CARRY    DISEASE. 

that  he  was  the  only  inhabitant  of  it.  There  was  nothing  there. 
'Who,'  said  a  rich  Greek  to  me,  'would  think  of  going  to  live  in 
such  a  place  as  that?  '  I  doubt  much  whether  it  is  the  Turk  who 
ha-  done  all  this.     I  think  it  is  very  largely  the  malaria." 

In  considering  carefully  this  suggestive  argument  of  Major  Ross 
does  it  not  appear  to  indicate  the  tremendous  influence  that  the 
prevalence  of  endemic  disease  must  exert  upon  the  progress  of  mod- 
ern nations,  and  does  it  not  bring  the  thought  that  those  nations  that 
are  most  advanced  in  sanitary  science  and  preventive  medicine  will, 
other  things  being  equal,  assume  the  lead  in  the  world's  work  ?  Who 
can  estimate  the  influence,  of  the  sanitary  laws  of  the  Hebrew  scrip- 
tures upon  the  extraordinary  persistence  of  that  race  through  cen- 
turies of  European  oppression — centuries  full  of  plague  years  and 
of  terrible  mortality  from  preventable  disease?  And  what  more 
striking  example  can  be  advanced  of  the  effect  of  an  enlightened 
and  scientifically  careful  attention  to  the  most  recent  advances  of 
preventive  medicine  upon  the  progress  of  nations  than  the  mortality 
statistics  of  the  Japanese  armies  in  the  recent  Russo-Japanese  war  as 
compared  with  the  corresponding  statistics  for  the  British  army 
during  the  Boer  war  immediately  preceding,  or  for  the  American 
Army  during  the  Spanish  war  at  a  somewhat  earlier  date? 

The  consideration  of  these  elements  of  national  progress  has  been 
neglected  by  historians,  but  they  are  nevertheless  of  deep-reaching 
importance  and  must  attract  immediate  attention  in  this  age  of 
advanced  civilization.  The  world  has  entered  the  historical  age 
when  national  greatness  and  national  decay  will  be  based  on  physical 
rather  than  moral  conditions,  and  it  is  vitally  incumbent  upon  na- 
tions to  use  every  possible  effort  and  every  possible  means  to  check 
physical  deterioration. 


INDEX 


Page. 
Abattoirs,  regulations  to  avoid  house  flies 32 

Anopheles  mosquitoes  (see   also    Mosquitoes,    malaria). 

disseminators  of  malaria 7 

suppression  in  Panama 22 

Ash  pits  containing  fermenting  material,  breeding  places  of  house  fly 31 

Bacilli,  typhoid,  longevity  in  milk,  cream,  butter,  and  cheese 27 

Bacillus  icteroides,  not  proven  to  be  causative  germ  of  yellow  fever 19 

Bacteria  from  flies,  census 29-30 

in  milk,  sources 28-30 

Bedbug,  a  carrier  of  disease 7 

Bedding,  old,  in  ash  pits,  breeding  place  of  house  fly 31 

Bubonic  plague,  conveyance  by  fleas 7 

Cafes,  regulation  to  avoid  house  flies 33 

Carcasses  of  animals,  breeding  places  of  house  fly 32 

Cholera,  Asiatic,  carriage  by  house  fly 7,27,34 

infantum,  carriage  by  house  fly 29 

morbus,  carriage  by  house  fly 34 

Culcr  fasciatus= Stcgomyia  calopus 19 

Deaths  from  malaria  in  United  States 9-10 

typhoid  fever  in  concentration  camps,  U.  S.  Army 24-25 

yellow  fever  in  United  States 18,31 

Disease,  endemic,  as  affecting  progress  of  nations 36-38 

Diseases,  intestinal,  dissemination  by  house  fly 7 

Dysentery,  summer,  carriage  by  house  fly 27,34 

tropical,  carriage  by  house  fly ». 27,34 

Endemic  disease  as  affecting  progress  of  nations 36-38 

Excrement,  human,  breeding  place  of  house  fly 31 

Eye  diseases,  carriage  by  house  fly 34 

Fermenting  animal  and  vegetable  material,  breeding  placed  of  house  fly 31-32 

Filariasis,  transmission  by  a  mosquito 7 

Fleas,  conveyors  of  bubonic  plague 7 

Flies,  biting,  carriers  of  sleeping  sickness 7 

Fly,  house,  breeding  places 31-32 

disseminator  of  cholera,  Asiatic 7,  27,  34 

infantum 29 

morbus * 34 

dysentery,  summer 27,34 

tropical 27 

eye  diseases 34 

intestinal  diseases 7,27-28 

purulent  ophthalmia 7 

typhoid  fever 7 

tuberculosis 7,  28,  34 

legislation 32-36 

life  history 31 

relation  to  typhoid  fever 23-27 

suppression  feasible  and  all-important 30 

manure,  name  for  house  fly • 23 

typhoid,  name  for  house  fly 23 

Garbage,  breeding  place  of  house  fly 32 

collection  to  avoid  house  flies 32 

Hippelates  flies,  carriers  of  pink  eye 7 

Hog  hairs,  refuse,  breeding  place  of  house  fly 32 

Hops,  spent,  breeding  place  of  house  fly 31 

Insects  affecting  health,  publications  by  Bureau  of  Entomology 35 

Lunch  rooms,  regulation,  to  avoid  house  flies 33 

Malaria,  deaths  in  United  States 9-10 

dissemination  by  mosquitoes 7,8-17 

eradication  at  Ismailia,  Suez  Canal 16-17 

in  Greece 36-38 

39 


40  LOSS   THROUGH    INSECTS    THAT   CARRY   DISEASE. 

Page. 

Malaria,  in  Italy,  loss  therefrom 11-12 

Mauritius 11 

Reunion 11 

United  States,  history 9 

loss  in  United  States 9-14 

Italy 11-12 

mosquitoes.    (See  iVsophclrg  mosquitoes  and  Mosquito,  malaria.) 

prevention 14_17 

relation  to  agriculture  and  other  industries  of  the  South 13-14 

suppression  in  Havana 17 

Panama 21-23 

Selar.gor,   Federated  Malay   States 15-16 

Manure,  disposal,  to  avoid  house  flies 32-33 

horse,  breeding  place  of  house  fly 31 

rabbit,  in  ash  pits,  breeding  place  of  house  fly 31 

Markets,  regulation,  to  avoid  house  flies 33 

Milk,  sources  of  bacteria  therein :>  :;<> 

Mosquito,  disseminator  of  filariasis 7 

malaria 7 

yellow  fever 7 

malaria    (see  also   Anopheles   mosquitoes  i . 

suppression  measures 15-17 

yellow  fever,  suppression  measures 19-23 

Mosquitoes,  losses  in  general  which  they  occasion 8 

through  malaria  which  they  occasion S-17 

yellow  fever  which  they  occasion 17-21 

suppression  in  Panama 21-23 

Nations,  endemic  disease  as  affecting  progress 30-38 

Ophthalmia,  purulent,  carriage  by  house  fly 7 

Paper,  old,  breeding  place  of  house  fly 31 

Pink  eye,  carriage  by  Hippelates  flies 7 

Plague,  bubonic.     [See  Bubonic  plague.) 

Poultry-house  bedding,  breeding  place  of  house  fly .".2 

Progress  of  nations  as  affected  by  endemic  disease 30-38 

Hags,  old.  in  ash  pits,  breeding  place  of  house  fly 31 

Restaurants,  regulation,  to  avoid  house  flies 33 

Sanitation,  rural,  necessity  for  government  support 35 

Slaughtered  cattle  paunches,  breeding  places  of  house  fly 32 

Sleeping  sickness,  carriage  by  biting  flies 7 

"  Spotted  fever,"  carriage  by  tick 7 

Stable  inspection  against  house  flies,  probable  cost 33-34 

Stables,  regulation,  to  avoid  house  flies 32-33 

st<  gomyia  calopus  (see  also  Mosquito,  yellow  fever). 

disseminator    of   yellow    fever 7, 19,  20 

Stores,  regulation,  to  avoid  house  flies 33 

Straw,  old,  in  ash  pits,  breeding  place  of  house  fly 31 

Tallow  vats,  breeding  places  of  house  fly 32 

Tick,  carrier  of  "spotted  fever" 7 

Tuberculosis,  dissemination  by  house  fly 7,28,34 

Typhoid  fever,  a  "National  Reproach" 36 

dissemination  by  house  fly 7,  23—27,  34 

in  concentration  camps,  U.  S.  Army 24-25 

loss  in  United  States 30 

Vegetable  refuse,  fermenting,  breeding  place  of  house  fly 32 

Yellow  fever,  cause,  history  of  investigation 19 

deaths  in  New  Orleans 21 

United    States '_ 18 

dissemination  by  mosquito 7 

history  in  America 17-18 

loss  in  United  States 18 

mosquito.     (See  Mosquito,  yellow  fever.) 

suppression  in  Havana  and  New  Orleans 10-21 

Panama 21-23 


il|ii|iii 


